Hear! Hear! Using Latin or Greek plural forms for anything other than about five well-established words is pointless and pretentious. Heck, I’m in favor of eliminating most of English’s irregular plurals (what’s wrong with ‘oxes’ or ‘gooses’? Couldn’t we use our brain cells for something more useful than remembering a bunch of random, useless, exceptions to a standard rule?)
Well, I’m not sure I want to really go that far… 
Then we’d just have to use more of our brains to remember that we’re not doing geese or oxen anymore. Inertia’s a powerful force.
And I always thought it was the Toronto Make Believes.
If you’re going to say “Foci”, you owned an MMVII and an MMVIII …
When you have a charismatic you can make as many charismata as you want, automatically.
Why is the ‘accepted’ plural (the only one ever used) of sheep ----- sheep?
I would say Nos habuerunt Foci if I was speaking Latin.
Or We owned Focuses if I was speaking English.
Because shoop sounds silly.