For the next iPad, many people quote 'iPad3' as the name of it. I would say about 40% of the chance it will call iPad3, but I would give 30% of it as 'iPad2S'. It is indeed the 3rd generation of iPad, but I don't think it is out right to assume Apple use the numeric value as the name of its products. It isn't applied to Macs, iPods, OS, or even iPhone (I got to that in a minute). So, will that be applied to iPad, not necessarily. Why iPad2S is possible is because, based on the rumors so far, the upcoming iPad will have a form factor 95%+ same as the iPad2. The major difference in physical form is the more powerful camera. Also, the core would be quar rather than duo. That's somewhat in line with that of iPhone 4S upgraded from iPhone 4. So, iPad2S is a very possible name when it is relatively more an upgrade of a fine existing product. The rest 30% chance that next iPad would be called 'iPad 4G', cos it would be the first iPad that use the 4G technology.
iPhone4S is actually the fifth generation of iPhone. When it was about to be released, people, most of them, claimed that it would be an iPhone 5. But, oops, Apple named that as 4S. So, what make people think that the upcoming iPhone should be named as iPhone 5 when it will be in fact the sixth generation of iPhone. Would that be kinda stupid to call that a 5 when it is a 6?! I don't think Apple named its product based on major appearance change neither. Nevertheless, in terms of probability, I will only assign a 5% chance that it will be called iPhone 5. Rather, I would say that it will be 85% chance that it is called iPhone 4G, as it will be the first iPhone that use the real 4G technology, a distinguishable advancement from reception technology from the past. The other 10% would be an something like 'iPhone 6', though I kinda doubt it.
Let's see if I'm gonna be right or not later.