Have you considered picking up an HSPA+ Nexus 7? If so, AT&T's latest promotion might have what it takes to influence your decision. Customers who sign up for an eligible two-year data plan will receive a $100 bill credit on their freshly inked covenant. Sure, locking your unlocked device to a carrier isn't the most ideal strategy, but if you're into mobile monogamy and AT&T's services meet your needs -- then by all means you have our blessings. However, you may have to hurry up and pop the question, as this offer comes to an end on February 14th.
Update: We just confirmed with AT&T that, in fact, this credit applies to "all tablets that are activated with a new two-year wireless agreement with data (minimum $14.99 / month) plan or Mobile Share plan." Huzzah!
[Thanks to everyone who sent this in]