Ok...so yea, it IS wikipedia...and anyone can edit it...but i just thought Id post it anyway...
http://en.wikipedia.org/wiki/Arcee
if you scroll down to the...Movie Plot section...it states the following.
'Arcee and her sister units, Chromia and Moonracer, chase the Decepticon Sideways in a alley in Shanghai.'
I guess we all expected Elita-1 to be the named...but once more...this is wikipedia...so its likely to be false.