Count 'em, because RIM has now announced four varieties of its BlackBerry PlayBook tablet. As of today, we've got the PlayBook with WiFi + LTE and WiFi + HSPA+ models joining the previously announced PlayBook with WiFi and PlayBook with WiFi + WiMax. As such, there's a pretty good chance that your carrier will have a 7-inch dual-core PlayBook with the QNX-based BlackBerry Tablet OS on offer at some point in the future, no matter how it chooses to define "4G."Continue reading RIM PlayBook tablet now in delicious LTE and HSPA+ fla