Last week I bought a Macbook Air with 13" and I haven't been able to sit in front of it for that long, the resolution makes everything too tiny specially because I work on a lower resolution laptop the whole day and only use the MBA at night. I have no idea if I will get used to it or if I just have to return it. I've been thinking about how wrong the future is going to be to our eyes if we keep improving the resolution of screens when operating systems don't deal that well with it. (I use Windows 7 on the MBA and I can't just go for a smaller resolution because type gets blurred.)