Mucho Mobile: 20 Buzz-Builders At Mobile World Congress

OK, so it isn't a Mobile World Congress debut -- Research In Motion's BlackBerry Playbook was announced several months ago. But at Mobile World Congress, RIM did confirm that two additional versions of the PlayBook tablet, one for LTE and one for HSPA+, will be available, bringing the total number of PlayBook tablets offered to four. (Wi-Fi, WiMax, LTE, HSPA+ if you're counting.) RIM didn't confirm exact availability, save for "the second half of 2011."