Perhaps the YF-23 was the best fighter never to be ordered and put in production. To me the YF-23 looks more 6th Gen. Flatten those tail feathers and it looks pretty much like artists impressions of possible 6th Gen proposals (engine development contracts recently released). None of the R&D that went into the YF-23 has been lost, so it was useful from that perspective. There's some real interesting stuff out there regarding 5th Gen. Watched a presentation by a USMC fighter pilot on the F-35. He did a exchange on the F-22 prior to joining the F-35 program. He said the two least impressive things about the F-22 is its speed and agility - hinting that the whole stealth & sensor fusion aspect is the most important.
USA has learnt from the engine development issues experienced during the F-111 and "Teen" series fighter programs and getting well ahead with engine development. This is what is causing massive headaches for both the Russian and Chinese 5th Gen programs. It looks like the Russian Su-50 (PAK-FA) won't get it's proper engines for another 9-10 years. China is having to spend Billions to get its shit together with its failing engine program (not able to get the reverse engineered Russian copies to last a decent amount of time with the required thrust). Issue with Russia and China is not having a large foreign customer base to share development engineering and costs - as is happening with F-35.
Likely features of 6th Gen is that they will not have vertical tails (even more stealthy), they will be large (internal fuel only plus large internal weapons bay), there could be both manned and unmanned versions, they will have laser weapons for missile defence (currently being tested by both LM & NG). So if we all live long enough to see 6th Gen, it's looking more and more like Star Wars stuff!
