It might be worth noting that according to the MacRumors Buyer's Guide,
at 208 days since the February update the MacBook Pro is approaching the historical average of 215 days between updates. However, the last two update cycles were significantly longer (309 and 317 days).
The last four times Apple updated or introduced a Mac in Q1 (the MacBook Air and MacBook Pro in 2008 and the iMac and Mac mini in 2009), they updated it again in October. The MacBook Pro and iMac examples were redesigns, as October Macs are wont to be. With the delay of Ivy Bridge and the later-than-usual introduction of the iPhone 5 I'm not expecting a redesigned MacBook Pro, but a pre-holiday bump certainly seems in line with Apple's past behavior.