Why the hell would you want to stop your project over the miniscule adversity of a pseudosimilar, vaguely-defined and -implemented platform that hasn't even gained traction yet? If that's enough to make anyone quit a project, I don't think the startup scene is for that person. For what it's worth, your project looks a lot more interesting. (Aside from the Flash.)
Yeah...on the one hand you want to keep your head down/keep the blinders on/trust in your gut and just plan on plowing through any obstacles that stand in your way. On the other hand, you want to try to keep your eye on the competitive landscape enough to make sure that you're not going heads down into a wall or that you're spending your time on the project that has the best chance for success.
Launching at the same time as a competitor creates more static in the press. I remember when the movie "Deep Impact" was announced close to "Armageddon". I thought to myself "Jesus Christ, this is too much". I don't think that whichever was the last one to hit the big screen was riding the coat tails of the other, or that the earliest one deserved my attention or money more than the last one.
Should Pepsi have called it quits, because they knew that Coca Cola were doing a coca beverage? Of course not. A competitor can be a pain in the ass in some ways, but it also makes for a great way to analyze your market and customers without looking inwards, which can be very difficult for anyone. If they gain traction, you'll know that there's a market.
If they die, you'll have their example as a cautionary tale; if you don't have a lighthouse to navigate by, navigate around the ship wrecks ahead of you.
I think he's annoyed that Convore launched a similar project and received some good press and community love (as little as it is outside the distortion field of the Valleysphere of Techcrunch and HN).
I always think of ReadWriteStart's mantra that "the early bird gets the worm; the second mouse gets the cheese".
"Is it important to be the first one out with the 'same' idea" is one of the many inane theory-crafting discussions that serve little other purpose than discourage people from launching.