if you meant macbook when you said notebook, then i'd go for macbook. I think ipad is really good for checking mails, updating facebook and twitter status and taking/editing photos - and oh, instagram too! but you can do all that too on macbook - twice the price though.
ipads are more for entertainment purposes.. you also cannot view all webpages on an ipad like you could on a notebook...
really depends on the use. Pad for sure for just surfing web, reading docs , email etc.Serious work related stuff (spreadsheets etc) - definitely still a notebook.
it depend on what the needs are? if i was a mobile person i will have an ipad it's because the simplicity and fast access to the internet.
Without no doubt I choose iPad. Actually, I'm crazy for that. I'm planning to buy new iPad with having best features of Retina display, I never think to live without my iPad 2. On traveling and outing every where we can use it and touched to the whole world by just one touch. It is also one biggest source of keep me entertainment always.