I came across the attack speed affix a few times, and the haste nature too. but never got it over 15%. I was more interested in doing damage and surviving than attacking faster.
recently, while getting my Ascension build back to where it was before I messed it up, I got stuck with attack speed again. well, I noticed that it caps out at 60%, and I thought, why not! so I maxed it out and WOW!
I had 2x multi attack and attack chance, with prismatic, and what a show! I quickly and as soon as I could, added another attack chance, and I am smashing all kinds of monsters. I am still in ascension mode, so I am having fun with this at m3 f110. what is really nice is the attacks are so fast, that my elements are overlapping on the monsters from the explosions from comets. with a high elemental crit, there is a lot of stuff going on.
I know not every build can use, or needs, a high attack speed, but I am adding attack speed affix to my list of likes.
for epic and higher monsters, they are getting hit so much so fast, sometimes they can't do anything for a moment, I think it is the freeze or stun, that I don't have to move around so much. but if they are fast enough, then even stunning/freezing them can't keep me from jumping around to stay alive.
one good thing about attack speed, it is some thing you can add to your build easily to increase your DPS early on in the game. just getting random drops with haste nature and normal or epic attack speed is easy. and attack speed goes well with early starter builds. wish I had paid attention earlier to attack speed. the only downside is attacking so fast means you are going through your MP faster, but that is something that can be dealt with in the early game too.
Edit: when posted, I only had the original +2 multi attack, not +4. going to be a lot more action when I can put in the other +2 multi attack.