Life was great until 9/11. 9/11 really transformed this country.
From my prospective, this is how I would summarize the early 2000's:
1/1/2000 - 9/10/2001 - The last of the "great era", very reminiscent of the (late) 90's. Napster/ Morpheus start the whole file sharing craze.
9/11/2001 - 12/31/2003 - Country changes completely. A time of fear. Muslim-phobia begins around this time. Dipset, G-unit, & the south are big on the hip hop scene. Style of Clothing is still pretty reminiscent of the late 90's.
1/1/2004 - 12/31/2006 - Birth of Social media (relative to social media today). Emo/ punk rock re-amerges as a major genre of music. Dipset, G-unit, & the south retain their influence on the hip hop scene. Skating, dunks, and the whole hype beast thing starts around the later part of this era.
1/1/2007 - 1/1/2010 - Country goes into a massive economic strain. Hipsters begin to emerge.