Yay, lets continue to be ignorant and completely ignore that Brawn had to let go most of their staff due to money issues and they continued to downsize for the RRA, which the top teams ignored.
So, as this topic get's bandit around a lot, let's take numbers (which you get from their Companies House filings)
2008 Honda F1 team --> 717 people (which I'm sure includes members of their engine team)
2009 Brawn GP --> 533 people
2010 MGP --> 487 people (so from the winning Brawn GP to MGP, they lost 46 people out of an ~ 500 workforce, not sure "MOST" descripts this situation correctly)
2011 MGP --> 526 people
2012 MGP --> the accounts have not been filed yet
to give some reference points
Lotus/Renault (Enstone) 2011 --> 500 people
Williams 2011 --> 493 people
McLaren 2010 --> 628 people ( +10 McLaren Applied Technologies, the folks looking after the FI gearbox)
RBT 2011 --> 605 people
Force India 2010 --> 302 people
McLaren & Force India have not filed their 2011 accounts yet, or they are not in the public database yet
MGP is on par with Lotus/Renault & Williams, give or take 20 people, maybe they are/were ahead in 2012, but McLaren & RBT ( and probably Ferrari) have ~ 100 guys/gals more on the books.