As of 2013, the top 10% of people had 85% of the wealth and the bottom 90% of people had 15% of the wealth.[1] FRED says the total net worth of households and nonprofit organizations was $79 trillion.[2] The population of the US at the end of 2013 was around 317 million.[3]
Crunching the numbers, we can determine that the top 10% had $67.15 trillion. If this full amount is distributed equally to every person in the bottom 90%, as the question states (let's call this the "kill the bourgeoisie" scenario), each person in the bottom 90% would receive $235,000 on average.
If we wanted to forcefully distribute the money while leaving the people at the top intact (let's call this "blunt force redistribution") such that the current top 10% has 10% of the wealth, then each person in the bottom 90% would receive $208,000 on average.
I would definitely consider this a life-changing amount of money.
[1] http://www2.ucsc.edu/whorulesamerica/power/images/wealth/Net... via http://www2.ucsc.edu/whorulesamerica/power/wealth.html
[2] https://fred.stlouisfed.org/series/HNONWRA027N
[3] https://www.census.gov/popclock/
Edit: Especially when you consider that this article[4] came out in 2013, a majority of people will be able to 1) basically completely exit debt and 2) start contributing substantially to the economy again. Not to mention afford college, afford healthcare, afford good food for themselves and their children, drop a whole lot of stress, and generally build their lives back up. There would be zero people below the poverty line. Who knows if the traditional refrain of "velocity of money increasing means inflation means collapse" would be realized in such a radical redistribution, and if a sudden and drastic shift such as that would end up hurting more than helping. We can only ever play the speculation game in matters like these.
The numbers in the main body reflect also the worth of nonprofits. Not sure on the proportions on that one, but even if you take it to be 10% of all the wealth (IMO an absurdly high estimate) the number still shifts to $187,000 per person in the bottom 90%.
[4] http://money.cnn.com/2013/06/24/pf/emergency-savings/index.h...