If you like the simplicity of the apple operating systems I would stick with the iPad. Keep in mind that they are releasing a medium sized iPad later this year, If you are looking at something with the screen size of a kindle.
Lyons is dead on here. Plus, if you already have apps purchased for your iPhone 4, many of them come with the iPad versions gratis (or vice versa), whereas if you purchase an Android tablet, you're certain to purchase all of your apps over again. Granted, I don't know how many apps you have, so this may just be a $5-10 issue, or this could be a $50-100 issue, depending on how much you used your iPhone 4.
As for iPhone 5 problems, most of the smartphones, regardless of manufacturer, have some sort of bugaboo or glitch in their first batch or two--not just Apple--that's why it's always prudent to wait a bit until they work out the kinks in manufacturing. It's kind of myopic to try and throw Apple under the bus when it's no secret that unless companies are willing to spend more money on QA before the units leave China, defects in first run units and using the public as beta testers is unfortunately the new normal. :-|
As for the iPad Mini, we should hear something this next week, IIRC, from Apple's press conference. I don't know where they'll come in with that price point, though--they kind of painted themselves into a corner with the current iPod Touch price points, unless those are going to drop soon.
Finally, if you do look at getting an iPad, if you know someone in education, a non-profit, or have a MicroCenter nearby, you can get 10% off the price.
