Facebook may be dominating the headlines this week, but don't forget about the little guys—or the no-longer-quite-so-little ones. Pinterest's valuation has jumped from $200 million to $1.5 billion thanks to a new $100 million round of financing. The Wall Street Journal notes that the news pushes the site into the "exclusive but growing club of Silicon Valley venture-backed companies" to pass the $1 billion mark.
The reality check: Pinterest has no apparent business model, makes limited revenue, and is unprofitable. But investors seem to see a path forward, thanks to big brands' (the Journal cites Whole Foods as an example) use of the site. Right now, they do so for free, but that could change. (Read more Pinterest stories.)