The convention I hold to quite carefully is to call the technology "BitCoin" and the money itself "bitcoins". This is largely so that even at the beginning of a sentence it can be clear whether I am referring to specific coins or the technology as a whole. It is an arbitrary choice, but I feel it improves communication of the concepts.
"BitCoin" appears as a gross abuse of the generally consensused and originally established "Bitcoin." I secretly (forget) established a filter to correct these types of abuses used at witcoin.