I had fiat sitting in MtGox and just today I decided it might be a good idea to convert a substantial part of it to BTC. I still keep a part in fiat, just in case the price goes much lower and I want to buy more at a lower price.

You might ask if I'm sure that the price will go up again. No I'm not. And I really don't know what will happen. My gut feeling tells me my decision is right. Let's see.

i think the main force behind alt currencies usually is the "Get-rich-quick premine" idea. however, alternative currencies might add features. bitcoin is an experiment, thus there might be flaws or shortcomings and these might be addressed by alternatives at present or in the future.