Yahoo! Big Thinkers India Series hosting a series of lectures on science, technology and the internet in India. The speakers are acclaimed experts from the Yahoo! International Team.

I did attend a session on Web Search and Online Communities, by Andrew Tomkins, Director of Search, Yahoo! and had some access to some interesting stats and insights into UGC- User Generated Content and Social Networking. Will upload photo later.

The amount of text based data that are publish through Social Networks are about 5-10 GB/day while the professionally published web content data is about 2 GB/day! The key thing is the content publised through Social Networking was negligible until recently.
The overall upper limit is about a whopping 140 Terra Bytes/day!

Crawling and indexing websites that use AJAX seems to be a challenge.