There's a bill floating around in the Michigan legislature that could allow the state to hold a January 29 primary (joining Florida). Then again, the bill could also allow the primary to be on Tsunami Tuesday (Feb. 5).
Here's what we can tell you about Michigan: Either party is prepared to hold a primary, a caucus, or even a convention in order to have a say before February 5. A lot depends on how Florida is treated by the DNC.
This has nothing to do with the primary calendar, but keep an eye on the North Carolina Democratic legislature, which could dramatically shake up the Electoral College playing field if it decides to award the state's electoral votes by congressional district rather than winner-take-all (a la Maine and Nebraska). This could take three to five electoral votes away from the GOP.