Originally just a rumor, it's now confirmed that PayPal will be offering PayPal Mobile, a service that will let someone send money via their cell phone in the same fashion you send and receive text messages. For a trial period, it's going to be tested with eBay employees, and later rolled out to other mobiles. The system isn't finished, so the details are not completely ironed out.
The goal, however, is to have a mobile payment system similar to a PayPal Debit Card (which you can already get if you are a PayPal member). This will be one among a very few pioneering attempts at super-fast payment, some of which have failed. This one is particularly unique in that an advertisement may have a code under it for instant purchase. Such as “text this number to order this product”. Interesting.