Personally, I dont understand why jetblue would ever need a first/biz class. They have the nicest staff, planes, service and the leather seats + the televisions and the leg room is, to me, like flying on an all first class airliner. However, if they ever decided to add the classes (which, again, they stated its against their business model) people would complain its no longer "cheap" and "low cost" because of course you'd expect those seats to be priced higher.

Edited: what works for airTran may not work for jetBlue.. and why fix it, if it ain't broke?