Bitcoin capitalization & blockchain vs. block chain

Minor points, but, this book will probably set the standards. 

Issue 1) Bitcoin vs. bitcoin
I think  many people use the capital "B" Bitcoin to refer to the Bitcoin network, protocol, concept, etc while lower case "b" bitcoin refers to the currency units.

For example, I sent 2 bitcoins to Bob over the Bitcoin Network. 

There are some problems though: Bitcoin user or bitcoin user? Bitcoin address or bitcoin address? Bitcoin wallet or bitcoin wallet? Bitcoin client or bitcoin client?


Issue 2) Blockchain vs. block chain
The original Bitcoin paper never puts the two words in sequence.  Satoshi's forum posts use "block chain".  Blockchain as one word is the name of a company.  I think we should stick with the "block chain" referring to the proof of work chain in Bitcoin and Blockchain to refer to the company.