Hmm... well, there's that brand new banner ad that now appears near the top of every page. I find it big, intrusive and definitely very explicit.
I know it goes away the instant I log in, but I generally don't do so until I have something to post. One thing I've always loved about this forum is its lack of distracting ads and images. It's clean and easy to navigate, and the strict rules on avatar and signature sizes help greatly to improve its look and feel.
But, hey, if the ads go towards paying for hosting and administrative costs, I'm all in support of them. My eyes will just have to adjust somehow.