What is a reasonable number of queries to Memcached per page? We do use getMulti to try to fetch what we know we'll need in advance all at once, but we mostly use getDelayed() (which is a two-part call with fetchAll(), and we do some other processing in between them.

Also, what is a reasonable number of keys to fetch at once? We have four separate Memcache servers now (soon to increase that by a couple) so the keys we're fetching from at once are going to be spread amongst different servers.

Seeing nobody has replied yet, you may want to try this question on SO (if haven't done already). If you do and paste the link here, I can upvote (and I guess some others will too).

I don't use SO. ;) Not because I'm against it. I'm just biased. ;) I'll just patiently wait here for an answer ........ la-de-da-de-da .....