Jesus no one has to throw out their old gadgets just because a new one is in stores. My iPad still works great and I plan to keep it until the battery dies or there's something much more appealing. It's common sense -- don't buy unless you need.
You get out with your rational opinions! We don't need your kind here!
...but yeah, it's true. My iPad 3 works just as well as the day I bought it, and didn't suddenly become a hunk of useless junk the day the iPad 4 arrived. It's not like the next best thing coming out shortly after you bought the previous next best thing is a relatively new concept in the world of technology. If you've dabbled in the PC scene at all, it was practically one of life's little truths back in early 90's to early 2000's.
When it comes right down to it, there's no real reason to buy the newest spec bumped iPad/iPhone unless they offer a hugely compelling feature to make it worth the purchase (such as the iPhone 5's larger screen or iPad 3's retina display). Only a select few developers will aim their software at the highest end product in the line, considering the vast majority of the user base will still be using the older hardware. If anything, it's better to wait for the latest and greatest model to show up then buy the previous generation at a discount. It takes developers at least two generations before they start taking advantage of a particular revs hardware, so you're not losing anything by doing so.