It's possible she could become a recurring character in the show, since Al Jean hinted the door will be left open for Sofia Vergara to appear in future episodes.
Oddities and/or Curiosities
In her first appearance (and only, thus far) "Teenage Mutant Milk-Caused Hurdles" , several curiosities occur:
She is introduced as Mrs. Berrera, though she is apparently single (obviously because the major premise of the episode: Skinner and Bart competing for her romantic attention). This is easily explainable by the possibility she could be a divorcee (or simply prefers using the Mrs. prefix), but a few other oddities thicken the plot.
First of all, she bears a striking resemblance to Gloria Jailbird (though the two characters are voiced by two different actresses). However, at one point while Carol is subconsciously talking to herself, she says something to the effect of "this is how I sound when I talk to myself". She does this in a voice curiously close to that of Julia Louis-Dreyfus (Gloria's voice actress). Not only do the characters appear and sound more than a little similar, Carol has the infamous Snake tattoo on the back of her neck at the collar line (Gloria is Snake's ex-wife).
One last tidbit: In the middle of the episode the trio (Caroline, Bart and Skinner) are in the playground and Skinner calls her Herrera, not Berrera. This is not only in the audio track but the captions on hulu also spell it with an "H" this one and only time on the episode (each and every other incident spells it with a "B").
Caroline Berrera is a beautiful, muscular women and everybody loves her.