bcc1234 - 11:24 pm on May 31, 2010 (gmt 0)
The problem with Bitcoins is that if it ever becomes mainstream, then botnet owners will use the CPU power of target machines to generate coins on a massive scale. That will devalue coins.
But the main problem is adoption. Unless I can find enough people who would buy those coins and pay me real currency, all those coins are useless. And I doubt the liquidity will ever be high enough to be useful in day-to-day applications.
If micropayments ever materialize, it will be either done by the banks or by some large company like Google.