If you can wait, then do wait but reports are saying that the haswell pentiums would be nothing but rebranded Atom Chips which should not perform that good in my opinion.
But since none of the reports are confirmed, hence you should take it with a pinch of salt and waiting for the next gen pentiums would be the better option.
Another thing to consider is that nowadays games are starting to take advantage of more than 2 cores, hence any cheap quad core AMD CPU would be better for gaming than the dual core pentiums, so if you can spend a little more, then do get a cheap AMD quad core, like the Phenom II X4 965 Black Edition which is a beast for budget gaming.
Otherwise, just wait for the next gen Pentiums.