The MBA is the best investment I have ever made. It will run all the programs you talked about just fine. I also use Word, Excel, and SPSS (at the same time) with no problems. The battery life is sweet and the SSD is super fast and you dont have to worry if you drop it. I have a 128gb and have had 2+ years of files, 2500 photos, etc and have not run out of space. Buying a computer with a CD drive is like buying one with a floppy drive a five years ago.
The only thing i would recommend is to max out the RAM. I have 2gigs and wish I had more. Not sure what they come with now as mine is the pre-backlit keyboard series.