I think it's a number of issues, such as the cars becoming more complicated (blue tooth, navigation systems, HID with complicated ballasts), etc. Honda is also producing more cars than they ever have before which strains factories.

I see the most problems coming from TL's and MDX's. Keep in mind they're also the top selling models, so problems per 100 vehicles still might be low. But those two models are also built in Ohio and Canada.

The RSX and RL are made in Japan and the TSX is made in the UK. I never see problems with those, ever.

EDIT: Most of the problems I see are with components to the vehicle, not the mechanical quality, although 2nd gen TL's, 1st and 2nd gen CL's and some MDX's suffer from transmission problems.