I used my exploratory parsing mechanism to look for [[File: ... ]] links to media files. I first ignored files with familiar suffixes like jpg, png, gif and pdf. This left lots of ogg and ogv files which I separated out as videos. This left a couple of oga files and some strange suffixes I didn't recognize like djvu, shivg and ext. I ignored them.

All total I found 878 video files on 707 pages,  227 of which were flagged as "Articles containing video clips".

I also looked for {{cite video ... }} templates and found 9,716 of them.

I'm scraping this information from an  enwiki.xml dump file downloaded Sep 22, 2010. It was 12,162,183,168 bytes uncompressed and contained 2,598,517 pages.

I'm attaching a text file with one line for each page on which I found (at least) one video. The tab-separated columns are: page-title, media-file, clips-flag.