This is technically the second episode with Bumblebee; She appeared very briefly during the lunch room scene in Deception (2004), but had no dialogue; Cyborg says they have met, but this occurred 'offscreen'.
This episode sets up events that are to be continued in Titans East: Part 1 (2005) (it is mentioned that Brother Blood is 'heading East' - and Bumblebee and Aqualad head out to track him down).
In the comics, Bumblebee (Karen Beecher) first appeared in Teen Titans (vol. 1) #48. Karen made herself a bumblebee supersuit and attacked the Titans to secretly help her boyfriend Herald (Mal Duncan) look good in front of the team. The Titans were impressed enough to offer her membership and she accepted. When the team broke up for a time, Karen and Mal got married and 'retired' from superheroics. They have returned to crime-fighting from time to time to assist the team. Bumblebee's abilities are derived from her scientific super-suit. She does not have any super-powers - or the ability to shrink - as she does in the animated series.