We know very little about these guys for now. JaJuan is similar to Bradley in that his shooting is much better than he has demonstrated in his rookie year. E'Twaun is a very confident player who doesn't turn the ball over much, and can score in multiple ways.
Doc has made it clear that this year was unfair to the rookies. No summer league. Extremely shortened training camp. The organization couldn't even get in touch with them over the lockout to monitor their progress and development. No practice means no time for Doc to see what to get from them. No way you can trust rookies if you can't even see them in practice, not on a team that's trying to win a championship.
I for one like what I've seen from both of them. Most importantly they are good kids who don't do bone-headed things and pay attention and learn. They will be fine in the future. Their future is not very stable however. Danny has a lot of chips on his hands. E'Twaun, Bradley, JaJuan, Two first rounders, Second Rounder and cap space.
With so many free agents on the Celtics Radar (KG, Ray, Green, Stiemsma, Bass, Pietrus) in addition to guys like (Hollins, Williams, Daniels, Pavlovic, Dooling) Someone has to go. I expect Danny to package a bunch of assets to bring in a big player. Josh Smith/Horford, Tyreke Evans, David Lee, Millsap/Jefferson, Igoudala are all possibilities.