An internal AT&T document comparing Pre to the iPhone 3G has been leaked, and, much to nobody’s surprise, AT&T doesn’t seem to really like the Pre.

The comparison chart isn’t what you’d call “objective”, and you’ll find plenty of negative adjectives like “limited”, “only”, “unproven”, “can’t”, and, wait for it… “very limited”. The iPhone side, however, sports “thinner”, “lighter”, “bigger”, “Global”, “fast”, “responsive” and myriad other feel-good phrases touting the iPhone’s superiority.

We can’t help but wonder, wouldn’t it do AT&T good to look at this with a little more, well… objectivity? Maybe some of the iPhone’s major flaws could be addressed by making a “comparison chart” sans narcissism. Better yet, ask Sprint to fill in the blanks on the right side, and AT&T could fill in the blanks on the left side. Everyone leaves with a bruised ego, but we all end up with better phones!

In fairness, the document does bring up a few real issues: the Pre’s lack of GSM capability is a big deal will certainly hurt sales domestically for frequent travelers.

Like we keep saying, though, May 17th (please!) will be the real moment of truth.