The people who actually care (i.e. you and I) already know about it. The people who don't care, have much bigger security concerns, IMO. Most people don't check for SSL when entering credit card information, so I doubt they would care about this if they thought it good speed up their browsing as much as Opera says it can.

edit: Though I do agree - I would trust them a little more if they were a little more outspoken about the security implications of what's going on.