NerfWiki. There's a whole slew of photos taken from this event that can be seen <here> too. Several fans have pointed out how many of these blasters look like they were designed as N-Strike Elite or Vortex blasters first. You can clearly see an "N-Strike ELITE" logo on the handle of the SideStrike for the ZombieStrike lineup that's been unveiled recently.
On the one hand, this looks like "let's launch a new lineup... but we only have a few original designs, so we'll just take some designs from the Elite line" quick fix... it could also mean that, later on, we'll have both ZombieStrike and Elite/Vortex versions of these blasters, simply recolored. Nerf isn't exactly against the recolor idea, as evidenced by the countless Sonic, Whiteout, Red Strike, and Clear series blasters (and a bunch I missed in that quick list) that they've released over the years. Heck, even the HammerShot for the ZombieStrike line up is a recolored and slightly retooled version of a Rebelle pistol!
Either way, there's a bunch of blasters headed our way to defend against the legions of the undead!