I agree never invest more then your willing to lose. But comparing bitcoin to yahoo is horrible really. Bitcoin is currency, you could make a argument its a industry but not a single buisness. And Yahoo had competition. Bitcoin does not really have competition as main crypto.
I disagree. Bitcoin is a currency that many, many people buy as an investment. All you have to do is read this site to find that out.
Whether an "investment" has competition does not mean much. An "investment" has to be shown as trust worthy and a future. It is too early to say that Bitcoin is either trust worthy or that it has a future. I'm not saying that it does not, but what I am saying is that Bitcoin will follow the principles of an investment for success or failure.