Keith Rabois slides his way to Square

Less than a month after his previous company, Slide, sold to Google, Silicon Valley mainstay Keith Rabois has landed in a new gig as general manager of Square, the e-commerce company spearheaded by Twitter co-founder Jack Dorsey.

Rabois made the announcement in the form of an interview with the Los Angeles Times. At Slide, he'd served as vice president of business development while also making a name for himself as a notable angel investor, and serves on the boards of companies like Yelp (which was nearly a Google buy itself late last year before the negotiations famously fell through). But he got his start back in the dot-com boom as an early employee of PayPal, and then jumped to LinkedIn before ultimately winding up at Slide.

Square, which uses a tiny piece of hardware to transform any smartphone into a credit card reader that can process transactions, needs this kind of expertise.

After a smashing amount of initial buzz in Valley start-up circles owing to Dorsey's marquee involvement and a Series A funding round that valued it at $40 million right out of the gates, Square's reception in the media has taken a turn for the lukewarm. Mainstream critics are concerned about the level of risk and potential for fraud, and early versions of the product have been plagued by both hardware and software glitches.

Perhaps the biggest concern is the competition--a profile of Dorsey in Sunday's San Francisco Chronicle talks about rivals on behalf of giant companies like Intel and VeriFone. As one of the Valley's "PayPal Mafia," Rabois is well-schooled in how to break down taboos in e-commerce and personal finance from the perspective of a start-up rather than from a big corporation, and that's what Square is in need of at the moment.