It's way better than a blackberry come on. For non-power users this thing is excellent if you travel a lot.
I use my macbook pro as my main machine. I've only used the dvd drive a handful of times and could have an external for home use (I've never used it on the road). Only killer is the missing ethernet port but for $30 you can get a USB ethernet car from Apple so that's not a huge thing, at home I always use wireless but on the road I have had to use ethernet cables.
Battery is incredible, 5 hours with Wifi and Bluetooth? My Pro lasts me 5 hours but that's no wifi or bluetooth with those on it's about 3 - 3.5 hours.
And the harddrive may be slow at 4200 rpm but heck my full sized compaq laptop came standard with a 4200rpm harddrive (which I upgraded once it died off) believe it or not many laptops come with 4200rpm drives, it does save on battery as well.
I think the air is great for the avid traveler, I'd consider if I travelled more. I find my pro to be perfect though, small enough for travel and powerful enough to be my every day machine.