I made a google spreadsheet with the number of transactions occurring in the bitcoin block chain per month, and the total value of those transactions:
https://spreadsheets.google.com/pub?key=0Ar4FtkFP4j73dDQyY3ZJWjdhMlBkZEtTSFJTZm9ieUE&hl=en&gid=0
(click on the BitcoinTransactions spreadsheet; the first is just another version of #produced over time)
Looks like bitcoin is growing nicely; I'm not sure why the big spikes in July and October...
I made the calculations using my bitcointools python code:
https://github.com/gavinandresen/bitcointools/blob/master/statistics.py