It's safe to say PayPal co-founder Max Levchin and 500 Startups accelerator founder Dave McClure are probably not friends. Levchin told the Wall Street Journal in an article out last night that there's a glut of accelerators and me-too startups coming out of them.

Levchin said the current crop -- including Y Combinator and TechStars -- are "designed to reduce risk, while I plan to actively increase risk." Levchin is about to launch a company that works on what the WSJ described as "ambitious ideas" that most existing incubators don't encourage.

McClure's first response to the article came in a colorful tweet last night in which he rewrote the article headline: "RT @WSJ: Some Pussies Fear Glut in Tech Incubators, Others Say "Fuck That Noise" & Write Checks. http://on.wsj.com/u0JJ8T cc @500 @Ycombinator."

And late this morning he tweeted a more personal attack on Levchin and GigaOm reporter Colleen Taylor (@loyalelectron): "Dear @Mlevchin @LoyalElectron Every1 Else: Pls Stop Shitting All Over @500 Startups @YCombinator while u chase the Next Facebook. #kthxbai."

So far, Max Levchin has not responded to McClure on Twitter; he also has not tweeted about the WSJ article.

McClure followed up his post to Levchin and Taylor about 10 minutes later with this: " .@loyalelectron then no fucking reason 2 rip on @500 & YC end ur post. WTF? think i visit 20 countries / fund 100 co's bcz we think small?" and then tweeted, "sorry folks -- full of fire & brimstone this morning, not backing down on a goddamn thing today. #EatIt."

Taylor wrote a piece, published this morning, entitled "It's time for startup founders to think bigger" in which she outlined major tech trends like high-performance computing and 3D printing. At the end she mentions that most companies coming out of YC and 500 Startups are consumer-focused web apps, then says, "Here’s hoping that in the near future, incubators will look for startup founders who are taking real advantage of their new-found access to serious tech tools to build bigger and bolder products."

This isn't the first time McClure has gotten so personal on Twitter. He had a well-reported exchange of terse tweets with superangel Ron Conway last year in which he accused Conway of throwing superangels under the bus.

McClure has made 250 investments across 15+ countries. His most notable investments include Twilio, Wildfire and Sendgrid. The third 500 Startups accelerator class of 38 companies is currently in progress. [ see LAUNCH's coverage of the second class's demo day.]

In January, LAUNCH researched the incubator/accelerator scene and found 58 worldwide that focused on tech startups; the largest number of this group were founded in 2010. About half were in the U.S., and of U.S. states, California had the most with 10.

Incubators/accelerators launched in 2011 include health-focused Rock Health, Los Angeles-based Science Inc from former MySpace CEO Mike Jones, the Kinect accelerator (TechStars and Microsoft) and Gazelle Lab in Tampa.

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