FW1.5, which will be out on the 24th, will add new payment options for use with the PlayStation Store, among other things. On the payment side, the PS3 will soon allow for "Edy" system payments. This form of e-money requires an IC Reader/Writer though, which limits its use to people who own the hardware that supports Edy currency and know how to connect their readers to the PS3.
The update also includes Korean language support for keyboard inputs and more PS1 and PS2 games on their list of compatible titles. For most of us, the big news will definitely come in the form of an updated compatibility list, so we'll keep checking for the update when it's out. In the meantime, sit tight, and let's see what the US firmware update will be like once someone from Sony America tells us what's up.