[The DaveR]

ND, The article I linked leads with, "Income inequality grew significantly in 2005, with the top 1 percent of Americans — those with incomes that year of more than $348,000 — receiving their largest share of national income since 1928, analysis of newly released tax data shows." It also states, "The new data also shows that the top 300,000 Americans collectively enjoyed almost as much income as the bottom 150 million Americans. Per person, the top group received 440 times as much as the average person in the bottom half earned, nearly doubling the gap from 1980."

Additionally, it has data that confirms what you stated originally, namely that top tier income (top 10 and 1 bps of population) declined from 2001 to mid 2003 but have since rebounded back to 2001 levels.

Shockingly, there's this sentence in the article, "The analysis by the two professors showed that the top 10 percent of Americans collected 48.5 percent of all reported income in 2005."