Umm yeah..*** is prety much dead on.... carriers prety much decide if they get phones. Ovbiously OEMS have the final say , HTC ,samsung w/e could refuse a phone contract to a carrier for not meeting their needs or what not.... ( like AT&T can say we want exlusive acces tot he HD7 ,, HTC could say* NO. )
and just to add to what everyone said.
CDMA chips cost MORE than GSM/hspa Chips to make...
Back in the day Bell dint have ANY HSPA phones ( only CDMA ) and NOKIA stopped making phones for bell cause it was costing them an extra 100$ to make each phone for CDMA use. ( so they made a lot less profit then GSM )
now that was like 3-4 years ago . im sure cost went down, but still expensive. + CDMA chips tend to be a little bigger , maybe harder to fit in our new slim phones.