There isn’t a single thing in this universe that grinds my gears more than seeing a company “market” how bad their competitor is.
Now I’m sure the guys at streak.com are great, they might even have a decent product. But you wouldn’t know by this post (http://hackerne.ws/item?id=4597289 [Link is now dead]) which happens to be titled “Help take down Salesforce - join the team at Streak.com (YC S11)”. All that says is, “We dislike our opponents, you should too.”
When you decide that your best marketing strategy is to focus on your competitors faults, instead of on your strengths, you’re doing it wrong.