+1. Speculators or day traders, whatever you want to call it adds liquidity to the whole economy which is never a bad thing. A healthy part of a monetary eco system.
Only within reason. Bitcoin is so "liquid" you can barely use it for anything else as gambling. Im trying to buy a few videocards and I want to pay with BTCs that will be held in escrow, but how the hell are we supposed to agree on a price when the value fluctuates with 20% an hour?
For most markets, 25% speculation is healthy. Once you get >50%, the value of the underlying asset becomes secondary to the speculation and you begin to have a problem. When its 99% like with bitcoin, you no longer have a currency or trade facilitator, you have a casino.