You should know what it can't do.
It won't run applications unless its written for the iPad's OS. Of course, they are rushing to rewrite them, and you'll have to pay for it, when it exists, and why pay for what you already have, some of which is freeware?
For practicality, and far less money, a netbook will do all the Ipad can do, including better battery life, national digital access via your existing cellplan [ and the right phone if you need this portability, why pay for 2 accounts if you don't have a current iPhone] and wifi, but its not as elegant or slim. It costs 1/3 that of the iPad, has 10x more available memory, has all the interface slots built in that the iPad omits [ so it drives you to use the network, and thus, pay for what can be free] such as USB, firewire, memory card support. When you have all those iPad adapters dangling on your iPad it doesn't look as slim.
A Kindle is a better option for slim net appliance if portability is your concern. But for both the bigger issue is the kinds of plug ins they can interpret, for specific website you go to.
I current use an Acer Aspire one, with 10-15 hour battery life for non-network access, 6-8 hrs of continuous net surfing via wifi [ I leave it on all day, thus] 160G of HD storage, easy expandibility, its basically a laptop scaled down 1/3 the size, and it was $200. It runs SPICE, the usual web and email, loads encrypted VPN network dongles, and nearly all kinds of proprietary encryption decryption schemes used for secure communications, and because a netbook is simply a small power frugal laptop, you can be sure it compatible with most anything out there for a PC.