Imagio on multiple networks?

[findrivr]

New here, so pardon the query if its come up here a few dozen times already.

Think I like nearly everything I've seen and read about the Imagio; can anyone confirm that the unlocked versions are 'BI'; ie: enabled to operate in CDMA and GSM networks, alternately?

I want to buy an unlocked unit to use on my ATT account, but if I later want to try out a Tmobile acct to ditch ATT, or even go to Verizon, will it be capable of operating between the 2 networks?

I like the form factor, large display, gps and FM radio... and that it's not an iPhone!
....not to mention the win ppc platforms..