Samsung Focus S (AT&T)

Pros: Sleek design
Smooth Mango Windows Phone 7.5 OS
Brilliant display
Zune music service (lots of downloadable and streaming content available)

Cons: No expandable memory. I miss my 32 GB from my original Focus.
Flimsy battery cover (functional, but detracts from what appears to be a well designed phone).

Summary: We have other mobile devices that we use for app development and this phone / OS is a much more attractive platform IMO than any the other mobile device options.

It's a great device I just wish Microsoft would come up with some better advertising to speak to the masses about what's available from their current mobile offering.