Even if one doesn't plan to get the iphone 5, one should still wait because of it's impact on the market.
You expect the Android makers to drop their screen size significantly, rip out half their RAM, and reduce the clock speed on their processors? I'm going to go out on a limb and say not too likely. To say that Apple has had close to no impact on hardware would be giving them a bit more credit then they deserve.
http://www.anandtech.com/show/3794/the-iphone-4-review/1
That was when they launched the iPhone 4, they were below/matched the specs of existing Android devices at the time. Android phone makers aren't getting into a spec war with Apple, that's like Mike Tyson getting in a fist fight with Dakota Fanning right now. For all the hype over the "Retina Display" the most popular Android devices in the world have
reduced their PPI, and gotten applause for it for the most part(people want bigger screens more then increased resolution apparently).
You can make a lot of arguments over iOS and what they did or did not do, but iPhone hardware certainly isn't known for pushing any limits outside of battery life on a regular basis(yes, the iP4 pushed PPI, but the 3GS was the worst in the industry by a long shot).