I had an account once that was banned, but only because I disliked that account's name and asked the DeviantART staff to ban that one so I could switch over to this one. Other then that... nope. No bans. No warning. I've got a clean record (as of yet).
I've never been touched, really. Since I'm online rarely enough as it is. Eh, I just get on and check my messages and watches. And...wow..after a month I have like over 200-something...anyway, I've never really been banned, threatened or had any of my artwork deleted, honestly. Then again, I don't even remember what I put up anymore.
One is when the spammer kept spamming up one of my pages and the spammer reported the staff; lying to them and banned my butt there for no reason. He also banned some of my friends as well. I had to report the staff to unbanned me and ban that spammer because they realise that my account got spammed, so he banned him permently for
A) Lying to the staff
B) Spamming up one of my friend's pages.
Another one was I got flammed by the members of Kirby's Rainbow Resort (KRR) because I bugged them at the forums and have a revenged w/ someone because I was banned from KRR forums since 2005. But someone reported me and ban me to get rid of the Journal because people are flaming and kept commenting my Journal that I wrote. Later, everyone decided to leave each others' alone because the Staff doesn't want us to flame on my account page.