With iPhone 2.0 install you can now do a screen shot (or screen grab) much like a print-screen in Windows or Apple-Shift-4 in OS X.
Simultaneously press the Home and Power buttons (i.e. – press and hold the home button and briefly press the power button whilst the home button is held). The screen will flash white to indicate the screen capture has been done and you will find the screen shot in your camera roll in the Photos section, ready to be downloaded into iPhoto, etc When iPhoto loads the camera roll ready for importing, you’ll notice the screen shots do not have an associated thumbnail, just an blank empty thumbnail. Clicking the blank thumbs and hitting import selected still works though and they appear fine as PNG’s in the main Library.
Home screen right now: