I have to think its going to be ranged pets, as Storms is a messy set with lots of KB and scatter. Its going to be a massively powerful secondary for MM's as far as I can tell and will probably go about making a bot/storm MM once i have dabbled with a few Epics
Well, pets usually aren't unnerved if you knock back their targets, so I would not rule out melee pets that easily. 
On the one hand the KB from storm summoning will help ranged pets stay alive, but on the other hand the scatter will greatly decrease the effectiveness of their AoE attacks.
As a result, actually I think storm summoning might work quite well with ninjas and zombies and less so with robots and thugs. (Mercenaries will suck with any secondary, so I leave them out altogether. 
)
If it has eyes, you can blind it, if it has blood, you can make it bleed, if it has a mouth, you can make it scream.
I'm drawn to robots as well for some reason. That might be a mix of having never played them, or just that they look chunky enough not to get blown around in a big hurricane.
My MA IDs:
Fiend Space: 211464
I just see Ninja's Oni using Rain of Fire while you slap down with Gale (from above!) and Freezing Rain for some serious carnage Also a nice elemental theme going on too!
Necro also nice for theme (Banished Pantheon!) and Hurricane certainly handy.
I am looking forward to Ninja/Storm. It is going to be very hard to make it work, a KB set + melee is going to be chaos. But I am loving the challenge already ;-)
@Boerewors
I will try a necro/storm too, more for fun reasons than for huge synergy. But as long as the pet AI solution to a kocked back mob is, use crappy ranged attack then maybe close in for melee (usually only after a goto), storm will be yet another set that helps ranged more. So i expect a storm 
of easymode robo/storms coming. At least they will have to push some buttons once in a while, unlike the fotm robo/ff.
Ninja/Storm for that Tsoo vibe Might finally get a Ninja concept I'm happy with!
Would Thugs/Storm work?
Thugs would work since it is ranged. When level 32 comes around, you will have to be sharp on that Go To button for the Bruiser or you will have to watch him throw his rock all the time, which cuts his DPS by 80%
@Boerewors
Which pets would benefit most from the new /Storm Summoning?