In 2005, Flock launched amid extensive…and then is promptly bombed.

Released as an alpha (a dumb idea no matter how you try to slice it), Flock attempted to become the “social browser”. One of its many shortcomings is it tried to be all things to all people, which only confused everyone. While Flock is still around, it never recovered from its inauspicious debut.

Fast-forward five years and we’ve got another much-hyped social browser, Rockmelt. There are two things that differentiates Rockmelt from Flock. One, the world is probably ready for a social browser whereas Flock was likely ahead of its time. Second, Rockmelt is backed by Marc Andresseen, the guy who created the Netscape browser before it was swamped by Internet Explorer.

My first impression of Rockmelt is mixed. I guess the biggest hurdle is the tight integration with Facebook. To get Rockmelt, you need to provide your Facebook username and password, and provide Rockmelt with access to a lot of your data. As a recalcitrant Facebook user, this is far from ideal – it would be better to have a standalone download.

The upside is Rockmelt looks solid, and avoids Flock’s mistake of trying to do too much. It looks and feels like a Web browser, which may appear like a straightforward proposition but, nevertheless, is important given people will compare how it performs to IE, Firefox and Chrome. (See the screenshot below that displays a Facebook stream.)

It also has solid integration with Facebook and Twitter. You can post updates on Facebook and Twitter directly from Rockmelt, as well as check out your Facebook and Twitter streams, and see the status of Facebook friends within a stream that sits on the left-hand side of the browser. I’m not totally clear about feeds feature, which strikes me as a frill as opposed to something that will appeal to many users.

Rockmelt’s biggest challenge, of course, is trying to gain a foothold in the highly-competitive browser market, particularly given that Google’s Chrome has changed the dynamics by stealing Firefox’s title as the hot, new kid on the block.

There is no doubt Rockmelt’s usage and investment prospects hinge on its Facebook integration. If positioned and marketed properly, Rockmelt could become the browser for many of the 540 million Facebook users looking for a browser that meets their need to browse the Web and be connected to Facebook.

By becoming the Facebook browser before Facebook could create one itself, it seems like a no-brainer Rockmelt will eventually be purchased by Facebook.

Of course, this is the way Silicon Valley works when everyone is so connected. A nudge here, a wink there, a few million dollars in venture capital, and, voila, the next hot start-up is purchased by one of the Web giants.