3 days after you say you RBP'd it, it's still there - implying that it must be within the TOS to have that sort of thing there.
I'm personally against all commercial type links in in signatures, but FT's rules have changed over the years in that regard (for the worse, IMHO) - so, given that, I really doubt much will change in that regard (even from a TB perspective) and this will be one of the things detracts from the user experience of this website.