I also have both an Air and an iPad, and they work really well together as Michael has said. One thing he didn't mention was Air Display, which lets you use your iPad as a second screen over a wireless network. I've a MiFi, so with that I can have a two-screen setup with me wherever I am, and it works a treat.
My other trick is that both the iPad and Air go into the one case, a Booq Viper which is a hard case made for the Air but that happens to fit an iPad 1 with Apple case still on in it, at the same time. (admittedly the Air's power lead doesn't fit, but that's all)
Have my Apple and eat it? Most definitely ;-)