On average, how long has it actually taken for people to receive BTC sent? Based on the wiki, it says it could take anywhere from 10 minutes to hours, to days.
Do most people usually add a fee to speed up the transaction?
It depends on your definition of "receive". If you consider a pending transaction sufficient, then you can receive your BTC in seconds. If you consider "receive" to mean 6 confirmations, then it can take over an hour.