The 11" ultimate MBA is my primary machine and I love it. Sounds like I use it in much the same way you do. I have an SD card reader that is more or less the size of a typical USB flash drive for transferring pictures. I really wanted to finally have a built-in SD card slot, but it's not that big of a deal.
The only thing I found is that I no longer keep my photos on the machine itself. I have an external hard drive for backups (way more capacity than needed for the backup itself) and I have now moved my photos to that drive. So that does mean that I use both USB slots when transferring pictures. I sometimes will use an externally powered USB hub if I want to make use of the Y cable for the hard drive while also using the USB card reader.
I don't find the 11" too small for uploading photos or using sites/apps such as Picasa or Photobucket. I don't find it slow for browsing or more girl-friendly games like Peggle and Angry Birds. (No hard core gaming here.)
If you have to move the machine at all, you'll love the form factor. We travel a lot for business, but even picking the machine off the table to move it away for dinner... it really is like lifting air.
Hubby (in software development/consulting) has no complaints about switching from a decked out Pro to the 13" MBA. If he could have got a larger hard drive, he would have got the 11" himself.
As I said on another thread, if you're wondering whether you really need all the power of a Pro, then there's a good chance that you don't. And if you know that, although you like the thought of the most powerful machine, deep down you could probably be happy with a high-powered netbook that actually worked the way you would hope it did, then absolutely you could go MBA without any difficulty.
