It's just a raging asshole move online. If you were talking about cars, it might be okay for GM to copy something by Toyota, feature for feature -- because they'd still have to invest a billion dollars or so in reverse-engineering, designing, manufacturing, distributing, and advertising it.
But if you can just apple-C, apple-V your way into stealing someone else's brand value, it's a sleazy trick that adds no value. At best, this means that the next time someone has an idea like this, they'll be more likely to go after the dot-com -- and if they can't afford the dot-com, they may move on to their second-best idea instead.
If they copied HTML code, or graphics, then sure. But if they looked at the site and incorporated similar elements and wording, which seems to be what happened, I'd say "meh - it happens".
IMHO not getting the .com is a really bad idea. The best case scenario is you start paying adwords a ton of money to get the traffic. Worst case is probably what happened here.
But if you can just apple-C, apple-V your way into stealing someone else's brand value, it's a sleazy trick that adds no value. At best, this means that the next time someone has an idea like this, they'll be more likely to go after the dot-com -- and if they can't afford the dot-com, they may move on to their second-best idea instead.