Hello, Olaf from Coinbase here.
I just saw this thread. I'm extremely sorry for the trouble people here experienced using our site! I believe some of these problems stemmed from our slow customer support during the November/December time frame. We were swamped with the 10-fold price increase. We now have a much larger team - I want to address any outstanding problems. Please let us know!
PM me or email
support@coinbase.com - I want to work out any issues anyone is encountering.
Again, I'm sorry for any problems that occurred during the price run up. Let us know what we can do.