No.
1) The majority of the fanbase has never seen a Sting match, so why would they care about Sting?
2) If he works like he did towards the end of WCW, I want no part of that (get beat on a bit, then no sell everything to run through his trademark moves).
3) The last thing the WWE needs is to bring in another old guy to shove into the top of the card. Build new stars, don't keep dredging up stars from the past.
4) Allegedly, there's rumors that WWE talent is worried about cuts after the new year (1wrestling, so take it for what it's worth). But if true, I don't want to see talented guys who never got a shot get released to bring in Sting, who won't come cheap, and who won't be the draw that people are saying.
5) He'll probably draw some ratings out of curiosity initially, but that's it. He won't bring back the lost WCW viewers, and he won't bring in a lot of new viewers.
6) How long before he tries to bring in Lex?