Well...
FF-ness --> checked
Pro-ness --> checked
Tahap dewa dewi low light performance --> checked
AF speed for speedy CEO's --> checked
Red ring, useable focal length, image stabilization --> checked
Apa lagi lu mau?

With camera like this.. if photo don't turn out nice also must jump down from twin towers di.
If the above still not convincing enough, then consider that Pete Souza (official White House photographer) photographs Obama, world leaders and historically significant events using the 5D Mk II.
If its good enough for the White House, its good enough for any company
http://www.flickr.com/photos/whitehouse/71.../in/photostreamDo homework for you

Enthuasiast compact focal length vs aperture table.

Don't just look at the widest...
see the max aperture throughout common focal length.
All these sensor sweet spot less than ISO200 and more or less tops out (imo) at around ISO400 +/- 1/2 stops...
everything else is noise vs details.
Example... If I wanna shoot a portrait of bini/gf/mother/mistress
indoors in a restaurant.
XZ-1 - 50mm focal length, f2.0, ISO200.
S100 - 50mm focal length, max aperture f4 means my ISO have to go up to ISO800 to get same shutter speed.
LX5 - 50mm focal length, max aperture f2.7 means my ISO have to go up to ISO400 to get same shutter speed.
About the smearing.. depend on how you look at it. Yes, the XZ-1 jpeg smears but the girls like it as it blurs out blemishes

... and most compact smears (my Sony HX9V smears even more).. S90 smears less but the details is not there in the beginning. You can always shoot raw... and if you don't like/use Lightroom.. you can always run that awful bundled raw-editor... turn off Noise Reduction as a preset and then just apply to all your pics = kau tim.
+1
if canon, you can consider 5D as you wan FF and Pro... either MkII or MkIII... with the kit lens or with 24-70 2.8 L is a nice combination.
Added on May 14, 2012, 12:26 pmfor sports 7D is slightly better, but 60D can do the job as well. If you do not need the articulated screen, i would suggest you go for 7D.
if size is your concern, go for NEX 5N. although i was planning to recommend you NEX 7 initially, but it will slightly off your budget
Added on May 14, 2012, 12:30 pmsniper has done a good comparison for you. if technical aspect is what you will consider the most, then you can see XZ-1 always has the fastest lens in the "compact" range... personal preference: S100 (if you shoot more in jpeg) or XZ-1 (if you shoot more in raw).
how about 7D? basically, it is slightly cheaper but performs well though.. coz ive checked the price at canon, 5D cost RM8k for body only...
7D cost cheaper and can boost the lens line-up more with varieties..