The first release on the testing cycle that will culminate in the next version of Firefox was made available today. In other words, Mozilla released an early test of the next version of Firefox. Normally an Alpha should be approached with caution as they can be unstable, but this release seems to be fairly stable. Codenamed 'Bon Echo' (no, I don't know why either), it has several new features well worth a look. The improvements fall into two main categories; Bookmarks and everything else.
The Bookmarking system in Bon Echo has been completely redesigned, and is called Places. It's built on some kind of new architecture (SQL-lite) that apparently gives it better performance. It also enables the program to store more information efficiently. Each time a page is visited, the time is logged, and so it is possible see how frequently pages are visited over time. In turn, this allows clever features such as special 'queries'. In other words, it would be possible to create a query of 'My favourite 20 pages' and the Places system work this out for you. As in previous versions it is also possible to search the bookmarks, and don't fear because existing bookmarks will be imported into the places system when you upgrade.
Last release the development team spent little time on the UI, chosing to concentrate instead on the rendering engine (the bit that actually displays the site). This time they have worked harder on the UI, producing some good improvements, particularly in the area of tabbed browsing, where they've added a close button on every tab (although an extension was already available to do that) and clarified how they think users would like tabs to behave.
The development team is beefing up the security around extensions. If you aren't a Firefox user, extensions are little programs written by third-party developers which add functionality to Firefox. The Mozilla developers are concerned that extensions could be used as a way to gain control of the browser and ultimately execute arbitary code on a user's computer. This has not happened to date, and so the improved security features are primarily a precaution, but a wise one.
Feed handling has also been changed, with the wiki talking of features such as the ability to use Firefox to subscribe to feeds in third-party news readers, including web-based products such as Bloglines. I don't think this area is completely feature complete in 2.0a1, but with the involvement of players such as Microsoft showing how feeds are becoming more central to how users consume the internet, Mozilla is right to be treating it as an important issue.
In summary, if you are an enthusiastic Firefox user (like me), you should definitely look at downloading Bon Echo, as it seems to be perfectly stable and does offer some exciting new features. If you're yet to get excited by Firefox, download the current program, 1.5 here, which is still better than Internet Explorer 6 and 7 in my opinion, and probably Opera. At the moment the release is not linked to on Mozilla's website, but it can be downloaded from their FTP site here.