I started using Qik on Nokia Nseries devices, then tried it on the Blackjack II, and finally on my original Apple iPhone. I just received a note that Qik's live video streaming service is now available on several more Windows Mobile devices from HTC. The particular devices listed include the Touch Dual, Touch Diamond, TyTN II, Tilt, and SE XPERIA X1.
While I enjoy using Qik, I also use multiple devices from different operating systems and don't like that I have to deactivate and then reactivate each time I switch devices. I think a large number of people using Qik at this time are early adopters who tend to have multiple devices and hope that better support for multiple devices comes in the future.
While not officially listed, I tried to test Qik out on my new Samsung OMNIA and the Palm Treo Pro (HTC is the manufacturer) and a message popped up in the browsers that said my device was not yet supported.