You can break down Rush's discography more or less as follows (I'm excluding the live albums):

1. The first album stands alone. Neil Peart had not yet joined the band, and they sound pretty much like a Led Zeppelin clone. It's a great album, but bears almost no resemblance to the rest of the catalog.

2. Fly By Night, Caress of Steel and 2112 are the early prog period. The band had not yet introduced keyboards into their sound. The music leans strongly in the prog direction, with a number of extended pieces.

3. A Farewell To Kings and Hemispheres continue the prog trend, but with keyboards now included and a somewhat slicker sound.

4. Permanent Waves, Moving Pictures, and Signals mark a move away from hard prog to a more commercial sound. They're still just as exciting a band as they ever were, but they are clearly becoming more accessible.

5. Grace Under Pressure and Power Windows mark the beginning of the band's slide into serious 80s-ism. There are some great tunes, but the production is way too glossy and relies too much on keyboards. In addition, the compositions are beginning to lose their Rush-like edge.

6. After that, things just continue to deteriorate. Each album is a bit less satisfying than the one before, with the possible exception of Test For Echo, which was a minor, and short-lived, step up from Counterparts (where they tried to latch on to the grunge fad and failed miserably). Sadly, their latest, Snakes and Arrows, is one of the most disappointing albums I've ever listened to.

The documentary film "Rush: Beyond the Lighted Stage" is released on DVD tomorrow, 6/29. It won the documentary award at Tribeca, if I'm not mistaken... should be pretty good.