One of the barometers that I'm using is to try and sell goods here on the forum. Afterall, everyone here understands Bitcoin so if I can't sell here, then the rest of the world surely isn't ready yet. So far my result has been less than impressive. No minimum bid, 80+ views, no offers. I know my goods have value because I have a locked in price from Amazon as to what they would be willing to give me for my item.
Obviously one item isn't enough to make any sort of conclusion, but I think as I put more items up for bid, it will give me a better sense of if this Bitcoin truly is just for speculators or a viable medium of exchange.
The stories of so and so bought a car or house with Bitcoin is irrelevant to me. A guy bartered a red paper clip into a house. Doesn't mean I should go out and buy red paper clips. Anyway, that's one of the current metrics I'm using for my personal bullish/bearish long-term outlook on BTC.
Come back to make comments on this analysis of yours in a year. Then you can say you've really tried and took the time to see what this market will become.
Fortunately, we have a control experiment for this, when Suggester made many of the same arguments being made today on Feb 18, 2010:
http://forum.bitcoin.org/index.php?topic=57.msg390#msg390. I think his logic was reasonably sound, if not perfect, and many of the things he said have since come through (e.g., speculation and bubble/bust being the main thing driving interest and transactions for Bitcoin).
On a similar note to what CurbsideProphet is doing, I kindly asked the guy that actually runs bitcoinworldmarket.com if he could do a service to the community and tell us on a daily basis what his actual sales volume is (
http://forum.bitcoin.org/index.php?topic=28276.msg357205#msg357205). His original post expressed his concern about loans not being viable for Bitcoin (or any long-term deflationary scenario) and how this would choke business growth (for the record, my posts make it clear which side of that debate I take). He hasn't taken me up on this, but I wish some other serious merchants would (e.g. spendbitcoins.com). We can argue all day long about "YES YES YES Bitcoin will take over the world" or "NO NO NO it will crash and burn", but there's nothing like actual data to settle these questions.