John Gruber has an intriguing speculation that Apple will follow up the expected spring release of the iPad 2 with another upgrade (the iPad 3, presumably) in the fall. He's only making an educated guess here, but I like his reasoning. Here's his prediction for how Apple will round out the year:

So, here's my guess at Apple's iPad plans for 2011:

* An iPad 2, fairly soon. Say, a March announcement, shipping in the first week of April. Faster, more RAM, maybe more storage, thinner and lighter, a front-facing camera.1 Running iOS 4.3.

* iOS 5, announced at a developer event in March, shipping in June.

* iPad 3, shipping in September, announced at the annual iPod event. Running iOS 5.1, same as the next-generation iPod Touch.

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