IMO metallics for evening will always be classic (i.e., shoes and evening bags).
I think metallics for day can look good if they aren't overdone and subtle. I think the shiney gold/silver trend we saw a couple of years ago is mostly over. I hardly ever see huge, bright metallic bags anymore. If I see metallics they are more subtle metallic finishes.
IMO I think the bling movement that started the metallic trend is dying down. I know I'm sick of every bag being covered in lots of metallic, studs, zippers, hardware, etc. and think there are others out there who are sick of it too. I'm starting to see a lot of designers going back to simpler bags again.