Did just that myself earlier this year (crammed in three of those SEA-NRT B fares to lock in Plat in Jan.)

The plus side is you get two (or more!) cards as the computer will consider you dropped, even though you still fly with status for those two months, and thus when you cross each milestone you get an elite card.

If you're looking to keep status, and don't mind putting aside the time during Jan/Feb 2011, you can sit back for the remainder of this year, cash in your FEQMs after 1/1/2011 and then haul caboose to whatever elite tier you want over the next two months.

You'll be rewarded with status not only for the rest of the year, but the next one as well (2012) *and* if you were up for doing the entire thing again in Jan/Feb of 2013, you could earn status every other year without loosing it, if that makes sense...and assuming they don't change the rules on us.