Doubtful anyone in January, this is for at the end of the season.
I don't think VDS will be around next season with his wife's problems, so I'd be after a keeper. Kuszczak has done well in his run of games, but I don't think he's a future #1. The two German lads are my personal faves, Nueur has impressed me more in the little I've seen of the two of them, but Adler is ahead of him for Germany and is a Man Utd fan. Alternatively if we weren't confident in any of the younger keepers (or needed to save money), I'd go for Schwarzer to give us that solid experience at the back for 2 seasons or so until he retires.
Then I think we need to sign a fairly established player for either upfront or left wing. Doesn't have to be a superstar, but also can't be just a kid with potential. If Real do end up buying Villa either Benzema or Higuain would surely be off, so I'd keep an eye on that situation. Possibly Dzeko. Or for the left wing...well, no-one jumps out immediately. Ribery will probably be too expensive, so maybe just raid Spurs for either Modric or Kranjaer.
And if Hargreaves looks like he's going to be a write-off, it's time to bring someone in to act as cover for Fletcher.