Websites that defined the early Web 2.0 era (2006-2010)

Social media gradually rose over the mid 2000s, and then exploded in popularity in 2006. The prime years of this era were 2006 to 2010. Around 2011/2012 there was a decline, and by 2013, the era was completely over, replaced by mobile social media platforms like Instagram and Vine. But which websites really defined this era? Here are some examples for me

MySpace (quintessential website of this era of course)
Pre-Google+ YouTube
Pre-Timeline Facebook
Flickr
Picasa
Bebo
Digg
Photobucket
Club Penguin
Many Flash game websites like Addicting Games, Miniclip, and Armor Games peaked in this era
iGoogle
Last.fm
Megaupload