And that is exactly what is playing out with Bitcoin becoming a speculative investment vehicle rather than a currency.
Preemptive reply to those who think speculators cause the tx rate to increase (often an invalid comment thrown out in HN): no they don't. Speculators typically leave the coins in an exchange wallet (they are not sufficiently technically savvy or motivated to run their own wallet). Buying/selling on an exchange does NOT create a transaction on the blockchain.
Source? After the Mt. Gox disaster the recommendation I've encountered most is to have the bulk of the digital assets in your own cold wallet, and only trust the exchange with the assets you can afford to lose. Since the deposits are near instantaneous, there's really no good reason to entrust the exchange with large chunks.