You offering me a commission?
I own two sets, an analog Sony, and the Samsung B630, so we're kinda in the same boat. Had good luck with both of them. Have you checked out the EX500 and C630 threads? Better yet, check the TVs out in person.
When I compared the EX500 and the C630, both sets were in torch mode playing store feed, and I didn't play with the settings. So take my observations with a grain of salt. I felt the Sony picture was a bit richer, but the Samsung showed more detail in dark scenes. Aesthetically I preferred the Samsung. Bezel was thinner, and black all around. Set was thinner too. OTOH the Sony has better controls on the TV itself, with real buttons. Samsungs have those silly touch controls on the bezel itself, and they're hard to see.
I spent a lot (too much!) time agonizing over which set to buy last year. In 2009 I chose the Samsung over Sony. In 2010 I'm not sure. If you're viewing environment can handle a gloss screen (mine can't) I'd take the Samsung 650 over either of them. As the other poster mentioned, more pop.