There is a function in the World of Warcraft API UnitXP ("unit") that gives the XP, but this function only works for the player unit i.e.: you can only retrieve your own XP. They apparently nerfed that some time ago, as stated above.

As for reading the XP from some AddOns SavedVariables, that's not possible between accounts. AddOns that show inventory, or gold or XP for all characters always function for just one account.

However, using LibRpc (see that other thread ) you can make an addon that shows party members XP bars, given they have LibRpc installed. I'm making an addon at the moment to add party member XP bars to the party frames, just like partycastingbars does for casting bars. Hope I can get it to work .