The AmLaw Daily published two recent articles here (focussing on California firms) and here (providing the national picture) about how large law firms finished the year financially.
The upshot is that most firms were either flat or up or down by a few percentage points, which is better than many experts predicted earlier in 2009. The result is attributed mainly to firm cost-cutting measures (the lay-offs; starting associate salary reductions, etc.) Read both pieces to get the full perspective.