AT&T stores have begun receiving new micro-SIM cards compatible with the carrier's LTE 4G network, prompting speculation that they could be compatible with a new third-generation iPad from Apple ...

Straight Talk now offering AT&T 4G LTE compatible SIM cards. ... According to Straight Talk, their plans start as low as $45 per month for unlimited talk, text, and data access.

The new Micro SIM cards have started turning up in AT&T stores, although they haven’t gone on sale as yet. They will probably begin selling them tomorrow when the iPad 3G goes on sale.