They say it's the hardest hand to play, and I would have to agree.
Most of the time with jacks, you will be ahead preflop. However, many flops can come that will make your stomach turn.
A recent example at the casino in my city was $1/2, and I was dealt JJ in EP. I raised to $12 (that would be considered on the hefty side of online, but is pretty standard at my casino), and got 5 callers. The flop came Q 9 x, and I just check folded. One guy made a bet and showed one queen.
So, do you treat jacks like a middle pair and hope to mine a set? In cash games I think this may be my new strategy. Then if the flop comes all unders, I can make a bet, and people may call me with top pair figuring they are good.
I think for sngs it needs to be played aggresively, just because you need to make a move sooner or later.