the 465 is technically better than the 460... and by technically i mean before you overclock it.
if you plan on using stock speeds then the 465 will in fact be better. if you are willing to overclock the 465 or even risk bricking the card you can sometimes unlock a 465 into a 470 by reenabling parts of the chip. this makes the 465 a kind of attractive option but again there are risks associated with it.
all in all the 460 if more efficient and mroe overclock friendly for most cases i'd reccomend it... but the 465 might be the best option if you're a real tweeeker and wanna take some risks