We already walked you through the first beta of Firefox’s next major version 3.0, and today Mozilla released beta 2 for download by willing testers and impatient ‘fox users. The second beta plugs memory leaks (yippee!) and adds features like a new URL auto-complete display, smart bookmarks folders, and revamped download manager. Get more details about beta 2 goodness after the jump.

Notable beta 2 improvements from the release notes include:

* Location bar & auto-complete: type in all or part of the title, tag or address of a page to see a list of matches from your history and bookmarks; a new display makes it easier to scan through the matching results and find that page you’re looking for.
* Smart Bookmarks Folder: quickly access your recently bookmarked and tagged pages, as well as your more frequently visited pages with the new smart bookmarks folder on your bookmark toolbar.
* New Download Manager: the revised download manager makes it much easier to locate downloaded files, and displays where a file came from.
* Memory usage: Over 300 individual memory leaks have been plugged, and a new XPCOM cycle collector completely eliminates many more. Developers are continuing to work on optimizing memory use (by releasing cached objects more quickly) and reducing fragmentation. Beta 2 includes over 30 more memory leak fixes, and 11 improvements to our memory footprint.

Of course, this is a beta so you don’t want to move over to it full-time—unless you’re cool with some instability and incompatible extensions while the kinks get ironed out. The Firefox 3 Beta 2 is a free download for all platforms.

Firefox 3 Beta 2 now available for download [Mozilla Developer News via Download Squad]

Firefox 3 Beta 2