Mozilla's second alpha of Firefox 3.1 is upping the ante in the next-generation browser battle. So how do the main contenders stack up so far now? One thing's for sure, the Firefox team has taken note of Google's recent Chrome release and worked hard to make sure its offering can hold its own.

Mozilla had already claimed its 3.1 version could outperform Chrome when it comes to speed (and most independent tests show it at least tying). Now, the engineers have incorporated Chrome-initiated options such as the ability to drag and drop tabs in and out of browser windows. The second alpha release also adds support for the HTML 5 video tag, which gives Web developers expanded options for embedding video within a page. Don't forget, too, that Microsoft's new Internet Explorer 8 beta 2 -- released at the end of August and quickly eclipsed by Chrome's introduction -- is also vying for a piece of the pie.

Here's a breakdown of the high and lowlights of each offering and where it stands as far as a full release.

Contender #1: Google Chrome

The status: Windows beta released September 2. Mac OS X and Linux versions still under development and said to be coming soon. No indication of targeted full release date.

The good:

Reliability. Chrome's multiprocess architecture makes a bad Web page less likely to take down the whole browser.

Speed. Chrome loads fast and keeps your surfing super-fast.

Simplicity. Its clean design wastes no screen space.

Searching. The Omnibox lets you type search terms or URLs into a single spot and figures out what you want.

Privacy. Chrome offers an "Incognito" mode that lets you easily leave no footprints from where you've been.

The bad:

Privacy. Chrome's taken a lot of heat for its monitoring and collection of user data, some of which happens before you even hit enter.

Security. It didn't take long for users to discover vulnerabilities in the beta browser. Several of these have already been patched.

Reliability. Some sites and online services still don't work with Chrome.

Consistency. Because Chrome is build on the WebKit system, it differs from the dominant platforms that most designers focus on.

Support. Chrome doesn't yet have any add-ons or customization options available. It's yet to be seen how these, once developed, will compare to the rich options available for Firefox.

Contender #2: Firefox 3.1

The status: Second alpha build released September 5. Beta expected in the next month. Full release targeted for end of 2008.

The good:

Strong foundation. Mozilla's already built a loyal following with Firefox, and it doesn't intend on letting that go. With Firefox 3.1, you know you'll have a powerful library of add-ons and support already at your fingertips, not to mention the slew of other assets unveiled in Firefox 3.0.

Speed. Mozilla says its still-under-development TraceMonkey JavaScript platform will leave Google's V8 in the dust. The second alpha build revs things up, too, with added support for "Web workers" -- a system that lets multiple scripts run as background processes.

Competitive edge. Mozilla's developers have good reason to watch what Chrome is doing -- and work to match it, if not one-up it.

The bad:

Security questions. Some studies -- albeit, Microsoft-funded ones -- have suggested Firefox, with its frequent new versions, is more susceptible to threats than the other options.

Crash potential. Unlike Chrome, Firefox does not have separate environments for each tab -- so one rogue page can still take the whole program down.

Support. Firefox has worked hard to snag a small portion of the browser market share, and most early predictions show Chrome taking away more of its userbase than IE's.

Google's focus on Chrome will also take away some of its previous focus on Mozilla's development efforts. Will Firefox be able to remain a key player in the browser war?

Contender #3: Internet Explorer 8

The status:: Second beta released August 27. Full release expected before the end of 2008.

The good:

Support. Love it or hate it, Internet Explorer is hanging on to about three-quarters of the browsing market with its default status in all Windows machines. You know developers and designers are going to cater to it.

Security. With Microsoft at its helm, IE hangs on to a reputation of safe and reliable browsing.

Privacy. IE 8 was the first to offer a no-record browsing mode, branded here as InPrivate Browsing.

Searching. IE 8's Smart Address Bar offers similar functionality to Chrome's Omnibox, letting you type in URLs or search terms and taking you to the right place.

Added add-ons. IE 8 finally catches up to Firefox with a new "Gallery" full of third-party add-on options.. The bad:

Speed. Independent tests have found IE 8 to be significantly slower than the alternative choices. Resources. IE 8 uses a lot of memory compared to its competitors -- a factor that could considerably slow down the rest of your system.

Crash potential. While IE 8 does use separate processes for tabs, similar to Chrome's approach, it does not do so to the same degree

-- still leaving room for a total meltdown.

Competition questions. Can IE's add-ons reach the level of Firefox's? Already, some users are complaining of problems even getting them to work.

That's the lowdown on the battle's current status. Remember, all three of these programs are still early in their development, so many of the pluses and minuses could change as things move forward. One thing's for sure, though: This battle is on, it's growing fierce, and each of its contenders will do anything it can to win.