I believe rlparker stands firmly behind wp-super-cache.
I'd suggest database calls are the bottleneck in any environment, shared or otherwise. Considering you've taken them completely out of the equation with static pages is the best step toward stability. Having said that, there is still the quantity of hits generated by a slahdot to consider as any server getting 10k hits a second is going to meltdown fairly quickly and require load balancing.
With static content it depends on the ammount of hits rather than excessive script processing overhead and queued database calls. I haven't tested DH at all for concurrent connections piping large files but from what I've read in this forum you can have a couple hundred concurrents and remain viable. There was also a note somewhere that DH users have survived an occassional slashdot.
I'd reckon your video site would run okay.
Post a link for us when it's complete!
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