A better alternative is sharedtalk.com, you can also do voice chat there. I use that a lot, but in general the pattern is just to use this type of site as an introduction at which point you exchange Skype or facebook user names and then switch to that for the long term language exchange.
The real competition for this new site in my opinon, is therefore not any of these exchange sites, but Skype since the call quality is so much better than any flash based solution can achieve. They need to offer something special in order to retain long term users and not just be a site used to introduce language learners.