Besides the obvious problem of the volatile exchange rate there is just no trust in any of the Bitcoin institutions, if I can't trust anyone else to manage my Bitcoins I need to do it myself. I can do that, but it takes time and effort to maintain secure systems. The real kicker is if something goes wrong, its my problem. If someone hacks my netbanking details the bank will cover my losses.
So what does Bitcoin offer? it opens up transactions that would have otherwise been too risky. Irreversible electronic transactions are Bitcoins niche. However that fact makes it very difficult to acquire Bitcoins with reversible payment methods. This slows down the process of entering and exiting the Bitcoin market leaving you vulnerable to the volatile exchange rate.
I really want Bitcoin to succeed but at this stage there is no way I would use Bitcoin for a transaction unless it was the only option.