If you are defining "best" as that being the best picture quality, you'll find that a LED back-lit LCD screen, with localized dimming, along with a 240Hz panel speed will give you the best picture.
Now, if you define "best" by connected features or user interface or something like that, we'll it all boils down to preference.
Ultimately, I would suggest that you let your eyes decide. I work for Sony, and I would suggest to you our best, the XBR-HX929. It has the X-Reality PRO picture engine that optimizes all video inputs, be it HD from Blu-ray Disc to low resolution internet video. It also has Motionflow XR 960, which allows smooth viewing of fast action sequences like sports programming, action movies, and gaming. All that, and wrapped in Gorilla Glass by Corning.
But, don't take my word for it, or anyone's for that matter. Do some online research, check out some repurable reviews, and then go to retail and ask for a side-by-side "shootout" with your finalists. Play the same source content on each (bring your favorite movie or game), using the same settings and the same hookups. Pick the one that your eyes like the best.
Oh, and be wary of retail sales associates. They are often incented in ways that don't alway match up with your best interests.
Good luck!