In my view, the point here isn't that ideas are worthless, it's that ideas are worthless without execution - this guy had an idea, and didn't act on it, and then saw a very similar idea succeed.
I think ideas are very important, but I think persistence is even more important, and I like the fact that the initial idea doesn't need to be perfect since you can pivot (yes, another increasingly overused term!), e.g. Microsoft, Paypal, Flickr.