Even though Quake 3 is superior to QL, QL has done a great thing: it brought new people to quake. And without a new all-in-one client to maintain the 'click and play style' + running servers, I really doubt those would spend their time trying to figure things out.
Its a shame, really. One wouldve expected full time professionals from ID deliver much better content than part time volunteers, especially after 4 years of development. Wasted potential.
Galdov: By Q3, people are referring to CPMA, mod made by the community. It contains plenty of great features, that are not included in QL for no known reason. The disappointment comes from the fact that ID still didnt best a 7 years old mod and didnt add promised stuff (by SyncError in 2009) such as ladder.