I think that anything that is recorded outdoors (nature, wildlife, sports) shows up a lot better than in SD. Flicking back and forward between SD and HD shows this in many cases. Anything recorded in a studio is pretty much the same imho....

Also, you have to consider the improvement in screen technology over the last few years which has made SD picture quality rise. If you compare HD with SD from 5 years ago, you'd have no issue.

North America's regular TV picture is far inferior to the UK. Here HD really makes a big difference. I think in the UK the difference will be less marked.

No - I think it's ace. It really shows.

The SD signal from your Sky box will look great on your SD CRT display. The SD signal from your Sky box will look worse on an HD display but not anywhere near as good as an HD signal from Sky on an HD panel.

The difference between the SD signal on your SD display and an HD signal on an HD display is there but it may not be perceptible or deemed as worth the money to the lay viewer. The key difference will be depth of tone and richness of colour. Gamers and avid film viewers may relish the experience. Viewers of news and current affairs may not see the benefit.

The SD signal you're viewing on your SD display will actually already be better than it was a few years ago by virtue of the fact the the programmes themselves will have been made in HD and then down-converted to SD during broadcast. Tests have shown that the longer in the production process that HD is used the better the resultant picture even if the programme is eventually only ever viewed in SD. You can see a clear difference in picture quality for re runs such as CSI or Grand Designs as the programmes made the shift to HD production.

HD is not a con, it really does bring with it benefits in picture quality but all of that is perceptual. If you can't really see it yourself then it's clearly not worth investing in.

Before making up your mind though it'd be worth seeking out some HD material broadcast in the UK. Colour coding plus differing production values in the US may have made the HD experience there somewhat suboptimal.

Got my first glimpse of HD at the weekend at a relative's house. I own a pretty good SD TV yet I still found the difference absolutely staggering.

I found the difference neglible, except on nature programmes as mentioned above, however i do think it depends on your tv, mine although flatscreen is getting on a bit

in an a-to-b comparison. But when I am watching a great TV show in SD, the difference just passes me by.

I record stuff on my Sky HD box in SD so I can fit more on the hard drive and now the novelty has worn off, I rarely use the HD versions of the channels cos I forget.

Your mileage may vary.

The problem is now we have a lot of variables. SD picture has improved in a lot of case as the original was made in HD. This has closed the gap. Some HD programmes are not HD just upscaled SD so that closes the gap. However watch a sports program and look at the crowd in HD, it looks like real people. Look in SD its a smudge of colour.HD has to be the future but paying extra £10 to Sky Noooooo.

3D now that is a gimick and a con to justify higher set prices.

Is superb, you can see the revolutions and spin on the ball. In tennis games, you can see the thread pattern on the net.

As everyone else has said, older programmes and films still look perfectly acceptable in SD on a new-ish set. On a 10 year old set, you're probably going to notice a bit of a difference. Not as much as VHS to DVD, but still pretty good IMO.

Wouldn't buy a new tv set on a whim solely for the purpose of HD though...I'd wait until the old one was knackered before upgrading.

Digital imaging is a complex subject. Processes are now done on nearly all digital streamed video output. Frames are basically modified in various ways which can either improve (slightly) or degenerate them, depending on how well its been done. Digital techniques such as 'sharpening', which is an artificial process that is very easy to do, to make images appear more crisp, is now done on nearly all output. But it can destroy high quality source material if its overdone or done badly, and it often is. It pays no attention to natural lens 'depth of field' for example.

Automatic colour correction and saturation boosting is also something that I've seen done very badly. These are all very easy to achieve 'fake' processes that alter the natural colour and tonal qualities of an image. These processes also happen progressively at various stages - on shooting, on transmission, and the TV itself will also perform these processes. So by the time it finally gets to your £1000 screen, very often its been screwed around with so much that its very far from what was intended by the photographer.

While there are true imaging experts in the area of still images, in moving image, its still unfortunately all very new. The whole brand new area of HD, and the temptation to try and cheat by improving the base resolution of images artificially, is unfortunately a license to deceive. Its much easier to try and cheat with digital techniques than it is to get hold of true high definition source material.

Personally, as a professional who works with imaging, I would advise - hold off for a few years.

I won't if you don't mind.

Its like when idiot boy Dick Bacon said to Mark Kermode the best thing he's seen in 3D was golf coverage.

but pay closer attention to those medical ads. You never know what you may need...
Side effects may vary.