Hi,
My DS10 sounds alot like yours! He scored 142 on the verbal portion of the WISC IV, but had a low processing speed score (100). He hasn't been diagnosed with ADHD, but I wonder sometimes.
He likes video games, beyblades and manga comics. He was a very avid reader early on (reading 200 page novels in grade 2) but now seems to prefer comics and ghost stories. He has very little interest in school, needs to be coerced to do his homework and gets As and Bs. He also took quite a while to learn his multiplication tables (requiring bribes, etc on my part, which I don't like to do) but is excellent at math logic.
He considers himself to be an average kid. I have been feeling lately (since we had the testing done) that I'm failing him somehow by not finding a more stimulating environment. He was in a Montessori school and had lots of behavioural issues (writing letters of protest to the principal, staging demonstrations at recess, subtly trying to pull a hair out of a boy's head to make a voodoo doll, etc). I switched him to a regular public school (there is no gifted programming where I am) and the stricter, more structured approach has helped -- he hasn't had any behaviour issues at the new school, and pretty much does his work when he is told. But . . . he still says that school is a waste of time and feels that he is being forced to learn things that will be "of no use to him in the future".
So, while I have no advice, I sympathize!!