Nice scoop from @lizgannes and @karaswisher :

“Ben did not want anymore VCs,” said one source. “He wanted an investor that moved the company forward.”

Rakuten will presumably help advise Pinterest on turning their pretty pictures into purchases, as commerce is already starting to emerge naturally on the site.

It’s a good choice of partners in that regard. Rakuten is one of the largest e-commerce companies in the world, with a flagship site Rakuten Ichiba. It was founded in 1997 and had revenues of $4.7 billion in 2011. Its CEO is Hiroshi Mikitani, whose nickname is Mickey.

One the richest men in Japan, Mikitani is one of the best known entrepreneurs there where he’s been described as “Richard Branson meets Michael Dell.”

I'm fond of saying To the "A" round go the spoils.

Meaning, if you didn't get into Pinterest early -- like a16z, Bessemer Venture Partners, FirstMark Capital, and the seed Angels -- then you aren't getting into Pinterest at all.

An overnight success four years in the making means this:

For a long time, nobody wanted to invest in Pinterest. Then a tiny few did. Then everyone did, but by then it was too late for everyone.

Way it goes in Silicon Valley. Way it goes.

It only took Pinterest 3 weeks to raise $100 million: http://www.businessinsider.com/it-took-pinterest-just-three-weeks-to-raise-120-million-2012-5

Other notes:

• Pinterest refuses to bow at the alter of Amazon or Google.

• Why Pinterest is worth at least half a billion dollars.

• 100 of the top 250 Internet retailers aren't yet on Pinterest.

• "Pinterest for Commerce" startup Shopcade is growing 30% a month.