It stands to reason that Apple is working on the iPhone 5, but today's rumor-from-the-internet narrows down the release window. According to KGI Securities analyst Ming-Chi Kuo, quoted by MacRumors, the iPhone 5 will be released in September and the iPad mini will debut later in the month.
"Some dude on the internet said it" isn't usually a good predictor of the future, but Kuo has a pretty good track record with these kinds of things. He predicted that Apple would kill off the 17-inch MacBook Pro, and then they did. He was also one of the first to report on Apple using in-cell technology to make the next iPhone thinner.
I find the idea of an iPad Mini intriguing. If the idea is that Apple is creating a bargain version of its popular tablet, I could see how a lot of people would be on board... of course, if it's the same thing, only smaller, I don't see the appeal.