AppActions has released matchTag (http://www.appactions.com/en/matchTag.html) for Mac OS X (10.7.2) or higher. The free app can update the title information in an iTunes music collection and amend, either completely or selectively, the missing data from the iTunes Store.
It facilitates the iTunes ID that was written into the new file during download and allows for either individual tags or for the whole set to be amended or replaced. MatchTag also has an option to download a cover image thumbnail.