Macbook Air Vs. iPad

I've needed a new device to help with both writing and checking my RSS feeds as well as some various music music projects, and I have been trying to decide whether to buy an ipad or go full on and get the Macbook Air. I like that the Macbook Air is a full on computer and has more customability , but the iPad adds both ability to draw and do things physically with apps like Paper, and a much longer battery life. Thoughts?