This isn't strictly relevant to the LiDE 25, but an advanced search of VT returns no updates for the LiDE 35, and entering "Canon" brings up a messy heap of confusing updates, so here seems as good as a place as any, and the "discovery" may be useful to other Canon scanner users...

As a UK user, I've been deeply disappointed to have a barely functional LiDE 35 hooked up to my Intel iMac, especially as Canon UK site's most recent drivers date from 2003. On a whim, I checked the Canon US site, and found a suite of updated, Intel-friendly software from June 2007. This installed with no problems, and even caused the one-touch buttons to work again, which I certainly didn't expect.

I encountered a similar situation with a Samsung printer a few years ago too, so it might pay to keep an internationalist outlook when looking for new drivers...