I sell accounts regularly and have not received any negative trust for doing so.
I have seen a number of other sellers do the same thing and within the last several (~7 ish) months I have not seen anyone receiving negative trust for selling/trading accounts, although I cannot guarantee future performance.
edit:
Edit: Not clear what type of accounts you're referring to.
he is clearly referring to bitcointalk.org accounts (at least it is clear to me)
it is not against the rules to sell accounts although some people do not like this practice, however people seem to be more open to the idea as of recently