hey sfedi, if you dont believe me then pop up a first through third level guy. Lets stat up some mice and have them swarm over the guy. At these levels one does not expect an ac higher than 18 or so really. So, this likely gives them a pretty good chance to hit. 15 attacks (-1 because the aoo is likely to get it killed) means probably around 7 damage dealt. Casters and the like of first or second level might just be knocked unconscious, fighter types have a few more rounds. It is important to understand that useing a single spell to cause a ton of attacks to happen, even small ones, can have big consequences, especially at these levels.
Just for fun.
Mouse
Diminutive Animal
Hit Dice: 1/8 d8 (1 hp)
Initiative: +4
Speed: 15 ft. (3 squares), climb 15 ft., swim 15 ft.
Armor Class: 18 (+4 size, +4 Dex), touch 18, flat-footed 14
Base Attack/Grapple: +0/(not gonna happen, rolling isnt really necissary, just say it loses

)
Attack: Bite +8 melee (1d2–5)
Full Attack: Bite +8 melee (1d2–5)
Space/Reach: 1' ft./0 ft.
Special Attacks: —
Special Qualities: Low-light vision, scent
Saves: Fort +2, Ref +6, Will +1
Abilities: Str 1, Dex 18, Con 10, Int 2, Wis 12, Cha 2
Skills: Balance +12, Climb +11, Hide +20, Move Silently +12, Swim +9
Feats: Weapon Finesse
Environment: Any
Organization: Plague (10–100)
Challenge Rating: 1/8
Something like that at least

They are hard to hit, they only do 1 damage each hit but they hit pretty well. Sounds like a low level guys nightmare, a miniature swarm of mice.
As an attack spell this can actually be pretty nice. Surround someone by this thing and attack all at once. If your buddy is also attacking the guy you are pretty much assured to gain the flanking bonus

along with dealing a pretty good amount of damage.
At higher levels however it just doesnt do anything. But, comparing it with a summon natures ally 3 for d4+1 first level natures allies seems about right.
Lamoni: He tried to help but wound up doing the wrong thing. This happens all of the time. Sounds like the ability is doing exactly what it is supposed to.
Sure it sucks for the big guy, but that is how the ball bounces on occasion.
Also, of course I know that magic can do magical things. But then, feats are able to do things that strain believability as well. I dont see any difference there.