Yeah, you're right. It's there. I'm an idiot.
I think the problem is that it doesn't appear to be a general bonus and so once you navigate away from that first page there's no mention of it. Well, I couldn't find it.
I also seem to have been credited with an extra $20 when I deposited into Intertops which also made me think that maybe I (or they) had stuffed up somehow. This seems to be a $20 free bet which is stated on the intertops site.
Anyway, they responded to my email and it's all good. The lessson here is not to sign up for poker sites just when you're going to bed.
Sorry for contributing to the confusion.