I'm having an issue very similar to the OP's.
I've been lurking these forums for a few months now but decided to register now for some advice after seeing this post.
I'm currently on 10mb broadband but I fancied upgrading to 50mb, including the superhub.
I logged in to VM site and used the link
http://shop.virginmedia.com/existing...broadband.html
It states that there is free activation and installation but there is no mention of the price increase. When I continued to complete the order there was still no mention of the additional monthly fee.
The site said something along the lines of "If you have not had a confirmed price yet, don't worry. One of our advisors will contact you before your installation date to confirm you are happy with any price changes."
Ok, I thought, however I have still had no contact apart from a confirmation email to say that the engineer will be out this Friday to install.
I had called VM before ordering online but got through to a fairly unhelpful agent who seemed more interested in selling me Virgin Mobile than getting me the most suitable broadband deal!
Any suggestions?