I must say I was quite excited to get my hands on RockMelt, the 'social media savvy browser' - here are some first impressions:

• essentially it's Chromium with some very good add-ons
• its best integration is clearly with Facebook - I especially like the shiny Facebook Chat API
• it's stable enough for a beta, although it does seem to slow up my machine quite a bit
• I am quite fond of this approach to a browser, however it needs serious touching up if it's ever going to compete with the big boys
• I am going to keep playing with it, just because it makes Facebook Chat so much better

Is it a winner? Who knows. But it is something slightly different and at least it's giving the other guys one of those "why didn't I think of that" looks on their faces.

Firefox has definitely been my main browser for the past few years, and I'm glad to see some very visible improvements in its new 4.0 beta version.

I have played around with it a bit and the biggest upgrade by far is the actual interface. Although it does borrow a few things from Chrome (tabs are now above the address bar and it has a cleaner overall look and feel), it does bring to the table something entirely new and at a first glance very useful.

App Tabs make your life easier (and your browser windows less cluttered) by letting you choose the web apps you use most (see above, in my example you see Gmail, Google Docs, Google Calendar, Posterous and Twitter) and turning these into mini-tabs (displaying only the website's favicon) that permanently reside in the left-hand part of your tab bar.

Now let's see if perhaps this version will be able to keep up with my hundreds of open tabs...