Couple of my mates have one. Theyre no replacement for a laptop for proper stuff but for just browsing the web are great. Really easy to carry about. We were using it for planning a road trip and using gmaps.
This will not be the best tablet but it is the stepping stone for tablets now. They can be that thin and perform well and do a unique thing you can not quite do on an smartphone due to small form factors limitations but you are right Sam, these do not and wont replace a laptop.
People who moan about them in that way are just wrong because as of yet they are not supposed too.
Going to get your mum or nan something so she can email you and view the web and watch movies on or read a book on and actually be able to do it quite easily? - Ipad.
You can download things directly from the store on the ipad but you still need a pc or mac to set it up which is wrong, but once its going people can use it. Sit on the couch and just go do stuff.
Later versions and other tablets will include cameras and more so people can then skype call etc.
A lot of people do not need a PC/Mac or notebook/laptop for what they actually need it to do and so a tablet is perfect for this.
Most out and about trips you do not really need to take your laptop with you if your just going to read, watch some movies, show some images or a presentation to people and email etc.