I have been using it successfully for a couple of days now, and I have to say, it's just awesome for a first release!
Couple of things that should be addressed;
1. Is the location function in the application supposed to update the user's profile on the actual site? If so, that's not working properly.
2. Picture uploading - Although I am not having many problems, the other forum is showing a few people having difficulty getting this to work. The only issue I have had with it is the iPhone app itself closes right after the picture is sent to the site.
3. Some people are having problems using the app if they do not use the root domain in the Site URL field. If they have the site in a sub-folder or a 3rd level domain, it will not connect. If you use the actual root (ex. www.domain.com) it works just fine.
Most of the other functions are good-to-go, will report more as I play around some more...