I switched from a iPhone 4s. When I bought it I was unsure if it would be as good as the iphone, i was telling the sales rep I just want to try it, if I don't like it I'll be bringing it back and going back to my iPhone. That was 4 days ago, in that time I have come to LOVE THE HTC ONE X. Frankly I have had the last 3 iPhones and they lack many of the features the OE x has. The one x seems much faster, has a better graphical interface, more customization, widgets, camera is just as good if not better, bigger screen, almost all the same apps as iPhone or something very similar, it has free cloud storage and streaming from google play for my iTunes music. Sure a lot of things are different, but once you just go with it it's not hard to forget about your iPhone. Most things that require a jail break or a app for the iphone can be done on the HTC out of the box.
The iPhone 5 will come out in October and if the screen is actually bigger it would probably be 4in at the max. It may have one nre feature or two, Siri will probably launch apps, or not. Regardless it will still lack a lot of the features the one x has. Apple is very good at giving you minor updates on the exact same phone. if your biggest worry is that you can't take your paid apps with you then you should buy a iPad 2. You get the best tablet, iPad 3 is another minor update, and all your apps can be used on it. This will also liberate you from being chained to the iOS phone Eco system.
I think you should try the one x and if you don't like it just return it and get the next iPhone clone in october. If your willing to really give the one x a chance you will love it.