So far, the only difference between the old and the new Apple TV is size and price. The new Apple TV is really tiny and still has a built in power supply (!) and at 99 USD it is a very affordable device.
For now, it is only for sale in the US. Does it work in Europe? Yes, it works well with 220V and 50Hz and a European flatscreen TV.
Is there any point in using it in Europe? No, not really.
If you live in the US and have a US iTunes account or a Netflix account, then you can use the Apple TV to rent movies and TV shows. It's quick, easy and fairly cheap and the image quality is good.
If you don't live in the US and you have, say, a Finnish iTunes account, then there are no movies or any tv-shows available for rental. And in this case it is quite pointless to have an Apple TV. You may be able to circumvent the regional restrictions with a fake US iTunes account but it is cumbersome and if you are caught you might be cut off.
You can use Apples "home sharing" to stream audio and video from your own computer's iTunes library to your Apple TV but the device is just as picky as before about video formats with only certain variations of the MPEG4 video format supported.
Eventually Apple will secure the rights to distribute tv-series and movies in more and more countries but it will take years.
More interestingly and in a more immediate future, is the possibility that Apple will start making applications (apps) available for the Apple TV. It's built around the same hardware as an iPhone/iPod touch but without the touchscreen. With low price and free games and utilities the Apple TV would become a really interesting home entertainment system. Perhaps the Magic Trackpad that Apple recently started selling paired with an Apple TV would be the perfect way to to turn your TV into a giant iPad on your living room wall.
What do think of the AirPlay?
To me the most interesting part of the new AppleTV. If I've understood the concept correctly, it's more like pushing content wirelessly to (Apple)TV from iOS (and OS X???) machines than pulling the content from them. If pushing video works as smoothly as pushing audio via AirTunes, that could be the better way of bringing the web to the livingroom. At least I think that the Google TV approach is the wrong one.
I mean, that browsing the internet is not a social event, but sharing the found content is. Imagine a couple browsing the web using computer attached to the livingroom TV – yeah, ain't gonna happen. Now imagine them browsing the web using their own laptops/phones/pads and streaming the video/stills/etc. to the big screen when they want to share the moment – maybe not a huge hit, but a little bit more interesting scenario.
The same way I think that running apps on TV-set or set-top-box ain't the way to go. Everyone's got a phone in their pocket and a laptop on the side, and they both have a superior UI compared to TV-remotes. Again, if you need to occasionally get the app on the big sceen, why not just streaming it there?
But I don't know, maybe my view is a bit skewed. If you think families with kids, the whole family surfing experience might be a working scenario.
You have a good point, but I think we all have to let go of the basic idear that couples spend time together in front of the living-room TV at all. Very few do these days. We're all out and about, kids' hobbies, own hobbies, shopping, working, jogging... And if we are at home we are probably in front of the laptop doing tasks we brought home from work.
Couples are not going to be browsing together on the living-room sofa but they are not going to be watching anything together either. The living room TV is going to be used for on-demand content - be it video, web pages, games or other applications - by one person at a time trough out the day.
Yes, your phone or your laptop might be more convenient for these things but this way your living-room TV might at least be useful every now and then.