New phone from Roger's?

[Zyro]

The first of September my 3 year contract with Rogers is going to expire and be renewed from another 3 years by my parents.I get to choose what phone i want this time, and I want an android. I like the Xperia Arc because of the big, clear screen and timescape but I feel like it is too big and want another phone like it. The Galaxy S Captivate works really well, and the Nexus S looks just as good. Which phone is better in specifications and which one should I get. Also, will there be any new phones coming to Roger's this summer that's not too big like the Galaxy s2 . Thank you