Guy Kawasaki, Hal Varian and Ross Mayfield have joined the board of directors of Slideshare, Amit Ranjan, co-founder and COO of Slideshare has announced on his blog. Hal Varian is the Chief Economist at Google, Guy Kawasaki is the MD of Garage Technology Ventures and co-founder of Truemors, while Ross Mayfield is the co-founder and CEO of Social Text. Ranjan just confirmed to me that Garage Technology Ventures has not invested in the company; just that Kawasaki’s joined the board of advisors. Slideshare is founded by Rashmi Sinha, John Boutelle and Ranjan. The site allows users to upload and share powerpoint presentations on the web. They even have a facebook app.