If we really want some interesting discussion about Batman's stats, I think we need to set a standard for level and ability score generation. There is an astounding number of combinations that are quite valid... if one reads the particular issue the guesser is thinking of when he came up with the stats.
For example, say Bats is level 16 and he must be built with an average original score of 15 (total 94 points between 6 abilities, including 4 for level). Some people may consider this a bit low, but let's leave some wiggle room for Superman here! Yeah, statting out Superman is an even bigger can of worms (is this planet-pusher Supes or the one Bats trashed?). Bear with me.
Using these criteria (and the D&D ruleset, since I don't own all the others), I would stat him as follows:
Classes/Levels
By "straight D&D" rules, he'd be something like Rogue 7, Fighter 4, Monk 4. He clearly has many feats and skill points, and no supernatural abilities.
If Batman's DM let him tinker with class abilities a bit, he could be Monk all the way. Trading in all those supernatural abilities (including speed over 50) for some bonus feats shouldn't be too much of a balance issue. The class skills seem about right, though it is also clear that he has several cross-class skills such as Disable Device.
Ability Scores: Str 16, Dex 18, Con 16, Int 18, Wis 14, Cha 12.
Now to explain the "weaknesses". Biggest weakness first.
Bats is not a "people person". He has lots of money because his daddy had lots of money, not because he was a great salesman or entrepreneur. It should be noted that 12 is NOT bad, easily enough to attract a few ladies once that +10 situational modifier for wealth is added in!
Wisdom is a toughie. On one hand, his willpower is considerable. On the other hand, he is quite capable of making the kind of bonehead decisions that smart-but-unwise people make. I decided to keep his wisdom fairly high, but not terribly so, and say he did as much to improve his Will save as possible. A DM who lets him make his own monk class would help the will save out greatly (a +3 difference).
Finally, there's Strength and Constitution. He is clearly good at both, and the main reason they're not sitting at 18 is because I want to follow my own rules here! So I had to look at my thoughts on the villains he fought to determine what I had to knock down. Bats fights villains that are stronger and/or tougher than him fairly often even if toss out the superhumans (Bane and Killer Croc are still in human range IMO), but he rarely fights anyone who is faster or more intelligent. So Str and Con seem more vulnerable to being cut than Dex or Int.
Alignment? I'm not touching that question with a 10' pole!