It depends on what you want to use it for. What webpages you like to browse. Do you like flash sites? If so, an Ipad may not be for you. However, imo, it DOES replace an netbook. Netbooks are useless.
It is a future changing device. look at all the companies trying to compete with other tablets of various OS's.
If your worried about space being an issue or filling up your ipad...think of it like this...
Say your going on a trip and your going to pack your suitcase...your not going to take your whole house with you, right? Only the things you need to take on your trip. The Ipad is similar. When your going somewhere, you dont want to take your whole computer with you, you want to take only the things you need to have with you, plus a few more things for entertainment purposes. You can do so many things on the ipad that a netbook cant. Netbooks are worthless. I run my own computer business and I always recommend the Ipad. Netbooks are dead, imo. They do nothing worthwhile.
If your still on the fence and can wait awhile, Ipad 2 is supposed to be announced soon, maybe wait and see what the improvements are?
Hope this helps! If you need anything, just PM me.
Happy paddin!
FreeBird