My laptop is my primary coding machine. I also walk to/from work (well, not all the way, but quite a distance) which makes laptops with 15" and larger screens a bit unsuitable for me. Because of my recent back problem (no more heavy messenger bags!), I decided to sell the 13" MacBook Pro I've had since last year and instead get a top-of-the-line Air (though a refurbished one). Which I did three weeks ago. This was an absolutely correct decision. The Air turns out to be not only lighter than the Pro, but also (1) its screen is significantly higher-resolution -- the 13" Air actually has the same effective display size in terms of pixels as a regular 15" Pro, which is great for text/coding, (2) the screen is noticeably less glossy than on the Pro, which makes it easier to work in cafes or other places where I cannot control the lighting, and finally (3) even the charger is a bit more compact.

During the three weeks of use so far, I've never once needed an optical drive. Definitely laptop nirvana so far.