People hate it when I say it but I am going for a SwitchEasy PureAnti-Reflect. I have used it on the iPhone 3GS, iPod touch and iPhone 4 and they are the best. No more finger print streaks and no more mirror like reflections.
You do get slight smudges but they are a million times better to look at than the color altering smudges you get on glass. In addition the smudges disappear when the screen is on. And being able to see the screen instead of a reflection is another plus. The only down side is you get a slight grainy look to the screen.
Here is a comparison on my iPhone 4
Image
Image
With the iPad being a bigger screen it will be even less of an issue.