Bieber might be ok... if he was covered by Seether! Shaun Morgan can take any mundane crap, case in point his covers of George Michaels' "Careless Whisper" and Amy Winehouse's "Rehab", sound amazing. I even prefer his cover of the Beatles' "Across the Universe" more. Shaun slowed it down a bit and mellowed it out more. I actually think Shaun's version would be better to get stoned to than Lennon's.
As for Bieber himself though, the boy can sing. One morning my sister had on Good Morning America and he was on there performing. It was obvious he was singing live and he sounded a lot better than Adelle did at the Grammys. He has potential, but if he doesn't leave this poppy teenybopper stuff soon he's doomed to be merely a teen idol. He definitely needs to transition into straight up R&B and soon.