I've had my Samsung LE40M87BDX for 3 weeks now to complement my PS3 and built in Blu-Ray player, and must say it is a phenomenal set up. I began to look at 1080i TV's between £450 and £650 and then got greedy and wanted 'future proof' 1080p. Those looking for 37" screens due to space availability will be pleased to know that at 40" the external dimensions of the Samsung are equal to 37" Sharps and Toshibas at a similar price (and lesser quality). After much research I found that Sony and Samsung share much of the technology in their components, however Sony seem to want 25% more money for in my opinion a less attractive TV.
I am more than happy with the picture, contrast and asthetics of the TV. A instant comparison against similar priced TV's is check the contrasts, the Samsung delivers Jet Black against Brilliant white, not Charcoal Black over Milky white as many other sets do, this is very important if you are an avid gamer, or need a blu ray, HDDVD player or Sky/Virgin HD.
Any criticism, yes, when watching some television (Sky or terrestrial) the picture can look a bit 'pixelated' as the programmes were made for a 780 line or 480 line TV (imagine a slightly zoomed in 2meg pixel photo on a camera), but you'll get this on any HDTV of this screen size. I must also say that the sound quality isn't the best compared with Sony or Phillips (I did check) however it is good enough for normal viewing. If you combine with a cinema system though, which most people buying this price TV will have, this won't be an issue, especially with the 3 HDMI outputs/inputs and various other outputs it has. A USB port would be nice for plugging in cameras, but as a PC can be plugged into the TV this is only a minor inconvenience, and I use my PS3 memory card slots for photo viewing.
Finally I really had to justify to the wife (and myself) spending nearly £500 more on this than the 37" Hanspree set I was originally eyeing up. I personally work very hard, have given up a £100 a month smoking habit and watch/play an average of 20-30 hours of TV and Gaming a week (not even going into CBeebies and daytime telly that the wife and child watch!!!!). I therefore think it is worth getting the best you can afford without going silly, but for God's sake measure the room and where the TV will go cos to many people I know have bought 40-42" TV's which look daft in their 10ft x 12ft rooms. All in all think about your investment, this TV will be £600-£800 next year so don't go silly spending £2000 on a name and features you'll never need or use. Nice remote by the way, and if you want to be flash Samsung do a motorised wall bracket which links with the TV, but that's probably expensive!!! Hope you find this useful