Having seen what looked to be FCC approval for a version of the Palm Pixi - called the Palm Pixi Plus - with WiFi b/g along with EVDO Rev.A, there's now talk that both it and a Palm Pre Plus will be headed to Verizon Wireless. According to BGR's tipsters, the two CDMA handsets will both run webOS 1.3.5 rather than anything newer, which seems to suggest a launch would be sooner rather than later.
As for differences in hardware, those same tipsters say the "Plus" versions will be the same physical size as their Sprint counterparts. However there's no telling if Palm have made any changes inside; the addition of WiFi b/g to the Verizon Pixi Plus seems a given, but we're also hoping for a memory card slot in the Pre Plus.
Unfortunately confirmation of anything like that will have to wait until more leaks or an official announcement. Right now all we know are the phone's codenames: the Pre Plus is codenamed Russell, while the Pixi Plus is codenamed Romo.