I would say knights are better in blitz. Your opponent is less able to keep track of the knight's movement possibilties. A bishop's territory of control is more easily recognized so calculateing the moves of an opponent with bishops would be faster and advantageous in fast time controls.
better to have Knights in Blitz games?

Bishops are 3.20 a Knight is 3 exactly so Bishops are better.
I'm talking about Blitz, sir.

It does matter and knights are better in blitz ! Take it from someone who has played more than 50,000 blitz games ! Most titled players I talk about this with agree that knights are better in blitz than bishops.
So I'm pretty comfortable with my knowledge about knights and bishops material values. Knights are better for closed positions, bishops for open positions. A pair of bishops is worth more in particular (some say approx +0.5 points).
However, I was just watching an annotated Blitz Armageddon game by GM Alexandra Kosteniuk where she claims the following: "Antoaneta has the two bishops advantage. My knights have a lot of good squares ... and as we know in a blitz game its better to have knights... because its easier to play with them." Watch @ 4:30
Most of the games I play are blitz, though I have never really heard this before. Is it a known fact that knights are somewhat more advantageous in Blitz because of their ease of use?
-- Saccadic