This is a question posed to us on a reasonably frequent basis at the moment, and the answer....?
If you are going to be using this for only domestic reasons, then you may be better off with an iPad. If you are for example just browsing the Internet, using it for personal email, reading an electronic book*, then the iPad is probably your best option.
If you are planning to use it for more serious tasks, such as business email, word-processing, spreadsheets, or accessing your small business network from home, then a fast, good quality laptop would be most suitable.
There is, of course, nothing stopping you from getting both eventually, but an iPad is more restrictive in terms of 'what you can do'.
* If you want to read electronic books, get a Kindle instead... took delivery of mine this week and can highly recommend them.