Heretofore only available via carrier (namely Sprint, AT&T, and Verizon), Palm has just made its consumer-level Palm Centro completely carrier-independent by offering an unlocked version. It'll have quad-band GSM support (850/900/1800/900 Mhz) but no 3G (up to EDGE only). It has pretty much the same specs as the AT&T model, but will be slightly more pricey at $299 and sports a gray number pad instead of the green.
Other news coming from Palm is that all Centros (including this unlocked one) will be able to get the new version of Google Maps that has the "My Location" feature (which communicates with cell towers to approximate your current location; a little like a faux GPS). This new version will be available to most Centro owners tomorrow, unless you're a Sprint customer, in which case you'll have to wait until later this summer.