I agree... IMHO the 11" is simply too small for a full fledged laptop that I am going to be using all the time. I much prefer my combo of 3G iPad and MBP. For me it is the best of both worlds.
I do business and am in the field a lot and I find the iPad is lacking (at times), but this is solely due to App Store restrictions on the types of apps available. I do a lot of testing and it would be nice to be able to have all/most of the apps I need on my iPad, but Apple's not about to allow that currently.
I have considered the 13" MBA as a potential solution, but overall I find using an old & cheep (slightly modified) Sony VAIO running Backtrack4r1in conjunction with my iPad is the most economical solution for me currently.
That said, I would love a 13" MBA if it was given to me. In the end, it's too small (storage, ram, and a bit slow) for me to use as a daily laptop. It would be great if all I did was note taking, but it's just not enough computer for me. That's why I opted for MBP as a primary system, and use the 3G iPad for billing and light notes/research mostly. It's annoying at times carrying around multiple devices, but it is what fits my bill.
Point is that it is all about what you need/want from it. IMHO the MBA is an ideal classroom computer, but in my business it's just not versatile enough for me.