My own impression
My wife bought one. She'd rather have got the iPad2, but as we both already have android phones, I thought it would be best to stay android.
My positive impressions:
lovely bright screen (especially compared to similar tablets in the shop), very smooth and fast user interface. Excellent browser. Competent email client etc. Nice feel in the hand, and really pleasurable to use for casual use.
The lack of USB and micro SD bothered me as a techie, but honestly, as a non technical user, it would probably not matter much. If you want a more general purpose machine, then a laptop really is better for that sort of thing.
The negatives:
lack of video support in Skype (in fact skype seemed to bugger up rendering facebook on a web page bizarely until I uninstalled it).
No official facebook app. The samsung supplied social hub lacks features such as not being able to read comments on facebook updates.
No BBC news app for honeycomb.
The browser gets served mobile versions of many websites, as they detect andriod as the user agent, and direct you to the mobile optimised version. Not the fault of the browser per see, but annoying (anybody know how to change the agent string in the browser?).
As the browser is very, very good has a decent resolution and has flash, the need for apps is less important than on a phone, as typically the regular HTML site is fine. However, I'm pretty peeved at the absence of skype video, as the ipad2 bearing fanbois have it, and it's a natural on a tablet.
Overall, it's a nice alternative to a laptop for casual use, and not a bad way to consume catchup TV services. If you want an expandable general purpose device, get a laptop!