So is the Australian dollar's march through 80 US cents a cause for celebration about our economic might or time to bring out the worry beads for a fragile economy about to buffeted by another headwind?

The far from conclusive answer is, "it is a bit of both".

Why it is happening is also tricky to pin down too, but it is largely a combination of the US dollar getting weaker against just about every other major currency, as well as a renewed demand for Australia's raw commodities— most notably iron ore.

It was a more "dovish" than expected statement from the Federal Reserve that finally nudged the Australian dollar over the 80 cent threshold in the early hours of the morning.

The Australian dollar has been on the tear in recent weeks, but so have the iron ore and coking coal, up around 15 per cent and 10 per cent respectively.

Winners

Nothing new here. Those benefitting from a stronger dollar include travellers thinking about a trip overseas, particularly to the US.

Buying something from off-shore? Well, you'll get about 10 per cent more bang-for-your-buck than at the start of June.

The stronger Australian dollar should also provide something of a hedge against rising oil prices.

However, nothing is ever so simple in the fuel market and pump prices often bounce around oblivious to fundamentals.

Losers

Once again it is a bit more complicated than usual.

For manufacturers, a rising dollar is a double-edged sword.

Around 80 per cent of factories use imported goods in their endeavours, so when the dollar goes up those components become cheaper.

But then there is the question of competitiveness, and AiG chief executive Innes Willox says 80 US cents represents a "tipping point" for industry.

A recent AiG survey found 79 per cent of manufacturers say they are "very competitive" in the band of 70-80 US cents.

That number tumbles to 38 per cent between 81-90 US cents.

"So 80 cents represents a clear psychological point where alarm bells go off and businesses think about reassessing investment, export contracts and profitability," Mr Willox noted.

Farmers are also not enamoured by a rising dollar, but there is a quirk this time.

US dollar prices for commodities are going up, which is good news.

As well there has been no loss of competitiveness given the Australian dollar is moving in line with currencies of other big agricultural exporters such as Canada, New Zealand, Brazil and the European Union.

"It's not so bad this time," Tobin Gorey, the Commonwealth Bank's commodities strategist said.

"It is not doing too much damage from a competitive point of view, the dollar hasn't gone anywhere much against the other currencies, although beef producers may be losing a bit against a weaker [Brazilian] Real," Mr Gorey said.

Resources companies earning their living in US dollar terms would not necessarily be happy, but probably are not in a position to complain given the increased demand for their goods is, in part, driving the appreciation.

For the likes of BHP and Rio Tinto it is very much a volume game at the moment and their profits should hold up even if their margins are crimped.

The RBA is unhappy as well

The RBA could well be bracketed with the losers, because a stronger dollar is definitely not what it wants.

For the last year or so it has cut and pasted its venerable phase, "The depreciation of the exchange rate since 2013 has also assisted the economy in its transition following the mining investment boom. An appreciating exchange rate would complicate this adjustment", into rate decision communications.

Well, things are a bit more complicated now.

"Be clear that even though the move in the Australian dollar is associated with higher commodity prices, the RBA is uncomfortable," Westpac's Bill Evans said.

"The clear offset to services; manufacturing; and agricultural exports that we might expect from higher commodity prices is not materialising.

"Cashed-up mining companies are not reinvesting and are not lifting employment in this cycle largely because they are not convinced of the sustainability of the current increases.

"As such the higher Australian dollar is a challenge for both growth and inflation."

The ASX is wary too

On balance, the higher dollar is a slight negative to the ASX, but most of the pain — to coin a phrase — is 'lost in translation".

That is the effect companies earning US dollars, translating back them to Australian dollars.

The usual suspects here are the likes of Amcor, Aristocrat Leisure, Computershare and the health sector's big global players like CSL.

The beneficiaries are harder to find although Qantas generally does well, as long as oil behaves itself.

Escala Partners chief investment officer Giselle Roux said it is essentially a US dollar story and a bit overdone at that.

"Apparel retailers for instance placed their orders and hedged currencies six or nine months ago," she said.

"They face far bigger issues a than a 4 or 5 per cent shift in the exchange rate.

"On average, it is not a positive but it is not much of drag either."

The market did not look overly concerned about another step up in the Australian dollar with strong interest in the miners pushing the market up again.

Where is fair value for the Australian dollar?

So is the strength justified?

On the basis of the key drivers being a weaker US dollar and a lack of conviction over the prospects there, as well as firmer commodity prices, a stronger Australian dollar is entirely understandable.

Despite the terms of trade — the ratio of export prices to import prices — slipping in the second quarter, they look certain to accelerate.

"The levels we are tracking through the third quarter put the Australian dollar trade weighted index close to fair value on the RBA's model, which is presumably why officials have only expressed minor discomfort with the recent appreciation," JP Morgan's Ben Jarman said.

"Consumer goods import prices were very weak in yesterday's CPI data, and on the detail today, that weak momentum in imports should carry through to more CPI headwinds, particularly feeding in $A appreciation in 3Q," Mr Jarman said on Thursday in a note commenting on the release of the latest producer price index data.

BetaShare's chief economist David Bassanese has run his own model on the fair value of the Australian dollar and notes it is the direction in commodity prices that seems to matter most.

"[Iron ore] forecasts suggest a further modest decline in the terms of trade by June next year, though to levels that still remain well above the historical average," Mr Bassanese noted.

"At the same time, further, [modest] downward pressure on the Australian dollar is likely from an ongoing narrowing in interest rate differentials — assuming the Fed hikes rates at least twice more in the coming year, while the RBA remains on hold."

Mr Bassanese said on his modelling "fair value" will hold well above 70 US cents for some time — it was 76 cents in the June quarter — before falling back closer to 70 cents next year.

Crisis averted, if it indeed it ever happened.