Well bitcoin itself isn't maxed out but the sentiment given the current state of bitcoin IS maxed out. This means that in order for bitcoin to move forward, some significant and corporeal development needs to occur, and this is certainly possible. However, the level of effort needed for bitcoin to drop is relatively minor. Some simple event can occur, such as... mtgox enables withdrawals. Actually, merely the sentiment needs to reverse, which can occur via something psychological.
Some keywords we haven't seen in a while: mtgox, withdrawal, bankruptcy, hacker, worm, legislation, fork, capitulation, winklevoss, scalability.
Sentiment only affect the price for a while, the fundamental support for the price comes from the long term demand. Official recognition of bitcoin as a reliable long term store of value (digital gold) could be a breakthrough. If pension fund are allowed to invest in bitcoin, then we are going to see a huge amount of capital inflow
Currently I only watch bitstamp exchange rate, it is very clear that any kind of large sale (like thousands of coins) will push the price down for a couple of percent, but then immediately be bought back and push the price even higher, this is exactly what happened during this spring in mtgox, some large player are testing the market weakness before they go ahead and drive a rally