Damn, wish it were easier to get IPO shares as a retail investor... (then again Facebook fell on its face out of the gate, hard to gauge whether an IPO will have a huge pop on its first trading day).
The fact that they happen at all means the banks are not good at what they do, or they do it on purpose so they can distribute wealth to their desired parties.
The real story is that Twitter raised 1.8 billion in cash, the market is just a side-show.