Nothing from the Cubs yet on this -- and I wouldn't expect anything soon, because they're at the 40-man roster limit and they still haven't even officially added Nate Schierholtz, but the team has reportedly signed another starting pitcher:
Cubs agree with villanueva— Jon Heyman (@JonHeymanCBS) December 19, 2012
Another report says it's "close", and cites Heyman's tweet:
Villanueva is 29 and has been a part-time starter, part-time reliever for the Brewers and Blue Jays since 2006. Over his career he's been quite a bit better in relief (3.76 ERA, 1.23 WHIP in 245 appearances) than as a starter (4.80 ERA, 1.365 WHIP in 56 career starts). So maybe Theo and Jed envision him as a relief pitcher, maybe a long reliever -- although many modern teams don't have such a pitcher on their staff, I think it's a useful role.
Since we don't know if this is actually done yet, nor do we know any dollar amount, it's hard to judge. If it's a modest-dollar contract, it's probably a decent deal to get some pitching depth.