I would be all for it.
I think his age is a moot point, and adding him won't interupt the "Youth Movement". The fact that Glendenning, Nyquist, Sheahan and Tatar will be line-up regulars next season is a pretty good "Youth Movement". Having Iginla come in short term will instantly make the Red Wings a harder team to play against, but won't hinder the further youth movement, or the ability to retain good young players with a questionably large longterm UFA overpayment.
As far as the d-baggery, I compare it to getting Chris Chelios. Most fans didn't like the idea of trading for him because of similar reasons, but after he was acquired, he was quickly warmed to.
He's got some intangibles that would make him a benefit to the Wings. Despite his age, he can still skate and is coming off a 30goal/61pt season. Also, once again despite his age, he's quite durable. He's missed only 20 games since the play resumed after the 2005 lockout. He was virtually injury from 07/08 up until missing three games with a lower body injury this season with Boston. He'd make the Red Wings tougher to play against, give them a goal scoring winger and another leader off the ice.
If Holland found some way to retain Alfredsson for one more year, and also bring Iginla in for a year or two, the Red Wings could have a very dangerous offense. It would also give him the flexibility to promote and re-sign young players that are also in the mix.
I think what it would ultimately boil down to, is if Iginla would want to come to Detroit. He's obviously after a Stanley Cup, so he'll want to go to a team that gives him a chance to win one now. Then again, a lot of the big contending teams aren't going to have a ton of cap space going into next season after re-signing RFA's and such. For some reason, I can see Iginla going to Anaheim to replace Selanne.