The site noticed that the original iPad's A4 chip was called S5L8930X, the iPad 2's A5 chip was called the S5L8940X, and the recently leaked A5X chip was labeled as S5L8945X. Going from the A4 to the A5 chip saw a jump of 10 in the labeling but going from the A5 to the A5X only had a jump of 5. Thus, the site surmised that the A6 should consequently be called the S5L8950X.
Now evidence of an S5L8950X (A6) chip has been found in the iOS 5.1 beta.
Deep in the iOS 5.1 betas (as shown below) sits references to two next-generation iOS device chips: the previously discussed S5L8945X and this brand-new S5L8950X. While nobody has found this 50X (A6) chip in the code until now, we can report that both next-generation processors entered the iOS code simultaneously. This would seem to indicate that Apple has been working on two next-generation chips.
It unclear why Apple has two next-generation chips. Perhaps they were testing which one was best suited to the new iPad or perhaps the A5X is for a different device. Maybe the rumored Apple TV or an 8-inch iPad?
We should get some answers when Apple unveils the iPad 3 early next month.