Well, applications are now available to everyone on Hi5. Our application (iThink) is also available:)
First experiences are a little shady. Right now it looks like a lot of applications are having problems with usability. In other words, its hard for you, the user, to actually use the application. Sometimes it won't load, sometimes it will load and then dissapear, etc. All kinds of things.
But, on the other hand, I think that applications on Hi5 will be far more popular than on Facebook, MySpace, Orkut, or Bebo. From my experience, non-US users tend to be more active on applications like iThink, and Hi5 has more non-us users than any other app. So we shall see! But in the meantime, check out my profile and add the iThink application. :) Bye!