You can buy banner ads, otherwise no.
As an eBook Device and eBook Store company person, I can say that the moderators do a good job of keeping this mainly discussion. I cannot plug my company devices on here but I can buy banner ads which get good attention.
I will say that they are very fair and impartial on here. They always try to help but even IF you take out banner ads you cannot talk up your own products. I have survived a few warnings and now I obey the rules without question.