Problem 1.
Exchangers are pretty fucked up. Mtgox lags, bitcoin-central got compromised twice, bitcoin-24 is dead (?), others are crap.

Problem 2.
Transactions are way too slow to proceed.

Problem 3.
Transaction fees are repulsive, exaggerated and impossible to reduce.

Problem 4.
Transactions are not reversible (if I buy anything, I have no guarantee that I will ever receive it somewhen, and can't ask for a refund or file a police complaint).

Problem 5.
Even after 1 month I still can't use my wallet because it has not been synchronized yet...

Problem 6.
Prices are way too fluctuating (if I have something, I'd like to be able to buy the same thing, not being able to buy a pizza one day, and 10 houses with the same amount later on...).

Problem 7.
...