For both business and individual drones sizes.
Q How much RAM, processing power, and disk space am I getting per drone?
A You get 256MB of ram, aprox. 5GB of disk space, and one virtual CPU (as defined per joyent). This is only guaranteed to be exclusively used by your application if you buy a business plan.
Maybe also referrer to http://legal.nodejitsu.com/acceptable-use-policy
[faq] Added info about drones specs to FAQ, Close #76