You could argue that it isn't a good system because it places less value on the companies being traded and more on the effects of trading itself, but within the current system I think people have a right to complain about a poorly-executed IPO.
The reason that a 'bump' occurs is that money is being left at the table - ideally, stocks should exhibit no bump, because that means that the company has priced their stock correctly. Any bump means that traders are reaping the profit of the increase in the stock's value, and that profit is what the company was seeking to gain by going public.
Ultimately we'll never know what would have happened, but the negative ripple effects seem plausible.
The only way that a glitch on opening day would have a permanent affect on the stock price is if the stock price on Day n (for all n > 1) is conditionally independent of the price on Day -1 given the price on Day 0. In other words, the best predictor of tomorrow's price is today's price, and yesterday's price adds no new information.
This is a reasonable assumption, but if you believe that, it means you also believe that stock prices are essentially a random walk, in which case there is never any convergence to the true underlying value, even if the price starts at that true value (which it may not!)
Let's assume that stocks are not a random walk and are some reflection of the underlying value of the company (however you define that).
Even if there had been a glitch, on the first day, as soon as the real quotes start getting published and the information is symmetric all around, then the prices should start to approach the fundamental value, even if they don't converge.
If a week later, Facebook is still trading below the IPO price, we can assume either that the convergence process takes time (unlikely, given the volume of stock being traded) or that the underlying value of Facebook as a company has changed in the last week (unlikely, since there has been relatively little news about Facebook-the-company, as opposed to Facebook-the-stock).
"Even if their had been a glitch?" Really? 3x the open was postponed, followed by 17 seconds of no quotes/trades on ANY stock from Nasdaq, followed by a crossed quote from same exchange, followed by 3+ hours of no quote in FB from the listed exchange.
And the trading volumes are so high that I imagine we should expect convergence by now either way.
Are shareholders now entitled to a reward for going public?
Opening day is over. FB is trading well below the IPO price, let alone the high. Nobody can blame that on opening day glitches.
That means that the market would have clearly been more wrong to give it an opening-day "pop".