Kog Maw should keep his Attack Speed on W
What they do on PBE is
Caustic Spittle (Q): [new effect] Passive added - "Kog'Maw gains 15/20/25/30/35% bonus attack speed."
Arcade Barrage (W): Cooldown increased to 17 from 13/11.5/10/8.5/7 Ability changed - now "For 8 seconds, Kog'Maw's basic attacks gain 130/150/170/190/210 range and deal 2/3/4/5/6% (+1% per 100 AP) of the target's maximum health as bonus magic damage."
It kinda doesn't make sense they moved the attack speed bonus from W to Q.
I think the Attack Speed bonus should stay on W so it looks something like this
Arcade Barrage (W): Cooldown increased to 17 from 13/11.5/10/8.5/7 [new effect] Passive added - "Kog'Maw gains 15/20/25/30/35% bonus attack speed." Ability changed - now "For 8 seconds, Kog'Maw's basic attacks gain 130/150/170/190/210 range and deal 2/3/4/5/6% (+1% per 100 AP) of the target's maximum health as bonus magic damage." and even his passive is doubled when Kog Actives [W]