I'm pretty sure I have only heard and read the term adver-sleaze-ment in the last couple of weeks, and it actually turns up for some direct discussion here. Greg Sargeant says there that he's been using it "for weeks", but doesn't take credit for coining it. It gets basically no hits in a google search.
But I'm trying to think of other cases of blends where we basically infix a word to replace a syllable of the original word. That is, we don't just add a syllable here but we take out an existing one to keep the overall prosody and syllable count.
Surely this isn't new, is it?