As a very happy owner of an unlocked Novatel Wireless MiFi, both CDMA and HSPA version, all I can say is the news of the GSM/HSPA version arriving in North America has to be viewed as great news. This is the most amazing device a road warrior can own.
I own the 2352 which features 900/1900/2100 MHz as I am in Europe so much, but the 2372 is optimized for the USA, likely meaning that it may work on T-Mobile 3G on 1700 Mhz, but no specs are out one the Novatel site to that confirm yet.
Given the lack of T-Mobile nationwide coverage and AT&T's sputtering network until the upgrades are finished, the CDMA versions from verizon and Sprint are likely more reliable for heavy users at present, but if HSPA/3G is what you need, then the 2372 HSPA version is still not a bad option.
I hope to test one when I'm back in the USA.