I also run virtual copies of Windows, and it all runs like a dream.
I would assume that if I replaced the HD with an SSD, the MBP would be faster because then it'd have the processing advantage.
In fact, the 13" Air has the same resolution screen as the standard 15" Pro.
My ideal machine would have more than 4GB RAM. It could even come at the expense of a smaller internal storage, because I'd use an external Thunderbolt drive to store client stuff.
So I might be sticking with the MBP for that reason..
The only downside I can see is that only 1 external monitor is supported. After all, when you're traveling, the smaller the better.
The portable size is amazing. From time to time you'll catch me caressing it and whispering sweet nothings to it. I can bring it everywhere with me and I don't need a huge bag to lug it around. I use a protective sleeve, which offers a bit more protection than the other types of sleeves. http://www.hardcandycases.com/bubble-sleeve-macbook-air-case...
Have you had problems with HD Flash/Netflix?
http://bergie.iki.fi/blog/11-macbook_air-the_best_computer_i...
The savings in space and weight are significant when you're moving around. The 11" really isn't much bigger than an iPad. I have some pockets it can fit in.
The tradeoff is a smaller screen when you're on the road. The small screen has high-res and is quite usable but I'd rather dock to something for long-term coding work. But external monitors are cheap, so unless your work pattern involves constantly moving from new desk to new desk it's not hard to just park a monitor at every one of your desks.
I just bought a brand new 11" with a bigger SSD and the i7 and the only thing I wish was different was the amount of RAM. If it had 8GB RAM, then it would easily be the best computer I've ever owned.
The new ones are so close to perfect. I share your disappointment in the lack of an 8GB RAM option. I'm also a little worried about the Intel graphics, though I hear the HD 3000 is comparable to the nvidia 310M, which presumably is only a slight step back from the 320M in the 2nd-gen Air.
I have a previous generation 13" and I find I use the SD port often, which is missing on the 11".
I thought I would keep the MBP around just as a desk station but after using the Air, I just can't stand the slowness - perceived or real - of the MBP. I've stopped playing computer games, but as a coder and photographer (processing RAW with Adobe products), I've been incredibly happy with the Air. It seemed like a luxury purchase at the time but it's had a big effect on productivity in terms of my personal projects. I live in NYC and I tend to carry my laptop (with my fullsize DSLR) everywhere...I used to do that with the MBP, but many times would not just because it was too heavy of a combo. I pretty much take the Air anywhere I go where it's acceptable to have a messenger bag.
Also, I had thought about getting the iPad2...but, besides the fact that the ipad2's feature set wasn't that impressive, I found myself using the Air for a lot of portable leisure computing and using the iPad a lot less these days.