Ok, I just got my mbp. Pretty cool computer. My question has to do with the fonts, for example in email and Safari. The only resolution that looks good is the 1440X900 except I can hardly read anything. I tried upping the font in system preferences and also in mail settings, but it doesn't seem to do anything. Is it possible to change the text size when emails show up without lowering the resolution?
Unfortunately, there's no way to scale the font size for every font currently in OS X. You can adjust some fonts by using the View -> Show View Options menu in Finder and adjusting the font size. Font settings in individual programs will need to be set within each application.
The only way to universally scale the font size is to adjust the resolution, but as you've noted, LCD displays have a native resolution that they are designed to run at. When you go outside of the native resolution, you lose some sharpness and the aspect ratios are thrown off when you have a widescreen.
Keep in mind that it can take some time for your brain to adjust to a new screen resolution. I work as a network admin and frequently have to adjust users' screen resolution to 1024x768 from 800x600 because most applications are now optimized for higher resolutions. Inevitably, most people complain when I do this of headaches and not being able to read the screen. Generally, I'll check back in with them after looking at it for a few days and they don't even notice it anymore. It's just an adjustment that you have to make - kind of like getting a new pair of glasses.
I hope the same holds true for you. I know how you feel as I once had a Dell Inspiron 8200 with the high-end UltraSharp display. That display was (get this!) 1600x1200 on a 15" screen. So, the font sizes were horribly small - and as with OS X, you can't universally resize fonts in all applications in Windows. It took weeks to get used to that and even still, I found it uncomfortable long after the initial adjustment period. But it sure was nice when I needed to fit a lot of stuff on the screen at once!
Good luck and I hope you're able to make the adjustment. Unfortunately, small font sizes are a reality of high-resolution displays.