Can you give out negative effects if Bitcoin is regulated?
First of all, it will become like other things. And that's not good.
Secondly, it will lose all that is fascinating about it.
Spot on.
Bitcoin was made purely to be the first decentralized currency on the web. If it becomes regulated, we can all just kiss it goodbye. I'll be moving over to LTC, Doge, or heck even DarkCoin. Something where the legend will continue. I won't be participating in bitcoin if it becomes regulated. Not a chance.