With the 2nd level wizard utility power, Jump, if I use it on someone else and they perform the jump, and the jump takes them past or through threatened squares (or they are currently in melee), do they provoke opportunity attacks? It's a free action to make the jump. My feeling is that it does provoke, but would like some opinions.
Yes, they would be subject to opportunity attack(s).
Opportunity attacks happen when you leave a square adjacent to an enemy. The only exceptions to this are shifting, teleporting or forced movement (defined as a push, pull or slide).
The Jump power is an excellent example of causing movement that is not forced, so it will provoke the opportunity attacks.
The last note is that you cannot take an opportunity attack on your turn, so use this on that creature that's flanked between your fighter and thief buddies :).