Of the three mentioned in the original post...
I think the Sony one is a "budget" Bravia. It's also a bit "old" now, having been around since last year. Has had good reviews, though.
The Samsung one is more recent. The R8 range is the successor to the R7 range (I bought an R7 at Christmas... few months later, the R7s were obsolete & the R8s were out at the same/less money! Oh well... still an excellent TV)
The R8s have three HDMI sockets (apart from the ones smaller than 32", which have two)... something definitely worth checking when looking for a new HD TV (one is not enough...I'll be needing an HDMI switcher when I get round to getting a PS3, or an X360 Elite, as my single socket is taken up by my Sky HD box).
The Samsungs always get excellent reviews.
Toshibas are also very good, although I don't know that model.
I still say Sammy
