How is it possible to have a +8 reputation for an upvote? Is this a bug, or is it possible to give a partial up-vote? I verified, and there's 1 upvote and 0 downvotes, so somehow it must have treated the up-vote as 8 points.
Weird, for external viewer (like me) it shows you got 10 points:
As Geoff correctly said the real amount gained is 8 due to daily rep cap, so the display of 10 looks like a bug.