On Amazon.co.uk there's a 32" 1080p TV made by Samsung that costs £260. For £90 less you can get a 24" 1080p monitor, also made by Samsung. The TV would be useful because I could also use my Xbox 360 on it and combined with the larger size, the £90 difference doesn't seem like such a problem. But are there problems with using HDTVs as monitors? Are the refresh rates and response times typically lower, for example?

As long as the HDTV is 60Hz(or even better 120hz) and displays in TRUE 1080p(and not 1080i scaled up to 1080p) then you should be fine. The larger display area might mean you'd have to sit a bit further back though, and possibly a bigger desk/stand would be needed for it to be put on.

One should also keep in mind that TVs often have less resolution choices than monitors. My TV does all the main resolutions though. 640x480, 800x600, 1024x768, 1280x1024, 1600x1200 etc... It will not display 1280x960 and a few others. Still, it's worth being sure about if you're going to run old games on it too.

Refresh rate is mostly irrelevant for LCD (unless you want to use Nvidia 3D glasses), the main issues is that the TV will have a rather low resolution when compared with a monitor of the same size (1920x1080 for a 32" TV vs 2560x1600 for a 30" LCD) as a result you will have a big screen but with the resolution and screen estate of a 22", but the biggest issues is that both are tweak for completely different purposes, a TV is set to have movies looks good so it might take some serious tweaking for texts to looks good and working on it not killing your eyes.

Also you can plug xbox or PS3 on most PC monitors either with a HDMI->DIV or directly in HDMI if you monitor supports it.

My 27" HDTV only goes up to 1360x768.

Yeah, one main issue with using a television for a monitor is their lack of supported resolutions. You will find the odd game here and there that has to have 800x600 for menus or something and if you get the wrong TV all you will see is a black screen. A lot of TVs scale everything though, and those would be fine. Just make sure you know which you are getting.

One other thing you need to know about 1080p displays is that many old 4:3 only games have a max resolution of 1600x1200, which will not display on a 1080p television obviously.

I have been using a 28" Dell 1920x1200 monitor for a while now and I really love it. Dell is really good for monitors, even though their PCs are crap. I do want something in the 30" or higher range in the future though, when I have the spare cash.

Ive had great success using HD resolutions and timing though my ATI card... with my nvidia hardware i can never quite make it display right though a dedicated TV.

I have a 42" 1080p that i broadcast to though a 5770 and it has no lag and with ATi ive been able to "maintain" aspect ratio and play every game Ive tried.

that main issue is you'll need the make the TV the dedicated monitor, split screen between a monitor and a TV really kills display performance in the way of sluggish updates and some screen tearing.

What Gersen said. I have 42'' LCD and it works great for games @1080p, but it's near impossible to read regular text on it. And even for games if you don't tweak the brightness (lots of TVs have many kinds of picture enhancements, but that's usually only applicable for movies), it'll burn your eyes.

HDTVs are usually LCDs. Either LCD or plasma.

Probably as I see you addressed the higher resolution part in the first sentence of your post which I forgot to read.

I've got a sweet Samsung HDTV/monitor. Probably the biggest difference is that it has an ATSC tuner as well as several additional inputs for things like HDMI, VGA and component in.

That's part of why you end up paying more for that HDTV over the monitor. And part of it is that when they get larger, they get more expensive, even with other changes in specs.

This, check your inputs, if there's no DVI explicitly listed you'll probably get hosed with VGA. Also, it's the panel type that makes the quality difference, IPS are the best, if you can get one of those under 250 pounds I'd take it.