Hi,
I'm having more or less the same problem, the only difference is that I'm one of the guys that tries to educate CS students
Right now I have a PowerBook G4 (1.3GHz, 1GByte Ram, 17") and I'm looking for a new Apple laptop.
Being "super glossy" the MB and the MBP 15" are no choice for two reasons:
1) Giving presentations I'm used to "stroll around". I've checked the MBA and a MBP in my local store. It's realy harder to recognize things on the MBP screen as soon as you are some meters left or right near your laptop.
2) Some of my students have the new MB or even MBP. Standing behind them it is realy hard to see something on the screen of there laptops, thus it harder for me to give them advice. If I would use such a laptop it would be hard for my students to look at the screen of my laptop.
These "super glossy" screens of the MB and MBP are really nice if you really are in front of the screen and if you can control the position of the laptop (or the light) but as soon as you are not in front of the screen or more people have to look at the display a "not so glossy" screen is better!
So from my point of view I have two choices: A MBP 17" (nonglossy ;-) ) or the MBA (which is not so glossy as a MB or a MBP 15").
If you compare the weight of the MBA and the MBP 17" the MBA will win. For almost everything I'm doing now, even my old PowerBook is fast enough. Programming is okay, creating lecture with pdflatex (from time to time with Keynote) is fine. The only application that slows down my good old PowerBook is Word :-(
Both, the MBA and the MBP 17" will give me a decent performance boost ;-)
With 99% I'm going to buy a MBA, the only thing I that lets me hesitate is the fact that the MBP 17" will have 8 hours of battery live.
Best regards
Peter