The Galaxy Tab is available on all 4 national carriers (Verizon, AT&T, Sprint, T-Mobile). They just started selling wifi-only versions about a month ago
I bought one used (T-mobile) about 2 months ago for $275. While a 10" screen might be nicer for extended web browsing, there are definite advantages to a 7" screen.
- I can hold the device with one hand quite easily
- Very mobile... it fits in my pants pockets
- The 1024x600 resolution makes it sharper than both the iPad 1 and 2
I use my device primarily as an e-reader, but it has all of the codecs built in to Galaxy devices so it can play just about any type of video you throw at it (divx, Xvid, mkv, mpg, etc) without having to convert it or import it.
It has front facing and rear facing cameras, so it is probably a better overall choice than the original iPad.
Unfortunately, the US versions of the Tab are the only ones that don't let you use them as a phone.