Follow the money. If a company's investors are new to the business or the technology, you're probably looking at an overnight wonder. Most dot-coms would never have even come to the public's attention if they hadn't gone public, because many didn't have any product to speak of. Most would never have gone public unless they had been pushed to gain visibility by their bankers and other backers. Worse, stock prices were often kept high by restricting the supply of shares.
Technology still matters.
If an IT company is promoted by non-techies such as consultants, lawyers and accountants, hop off the bandwagon. That's simply not good enough. If a company shows quarter after quarter of losses but can't tell you when or how it's going to be profitable, run. Some argue that the economy and the stock market will come back, healthier and stronger. I also believe today's widespread havoc, caused by devastation in the stock market and the contraction of the tech economy, could have been avoided.