Just got a newsletter from bambuser (http://bambuser.com/) today and checked the service again.
It seems to have developed to a nice little qik (http://qik.com/) alternative within the last months.
I signed up in April 2008 but didn’t really use it. I think there was no support for my mobile back then. Anyway… now there is an iPhone app that you can install via Cydia, that means you have to have a jailbreak.