What is the difference between "I have to go now" and "I must go now"?

Hi buddy :

2012Sorching summer comes, in order to thank everyone, characteristic, novel style, varieties, low price and good quality, and the low sale price. Thank everyone

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$33 True Religion jeans, Ed Hardy jeans,LV,Coogi jeans,Affliction jeans

$30 Air Jordan shoes,Shox shoes,Gucci,LV shoes

50%Discount winter fashion :Sandle,t-shirt,caps,jerseys,handbag and brand watches!!!

$15 Ed Hardy ,LV ,Gucci Bikini

$15 Polo, Ed Hardy, Gucci, LV, Lacoste T-shirts

$25 Coach,Gucci,LV,Prada,Juicy,Chanel handbag,

$10 Gucci,Ed Hardy sunglasses

$9 New Era caps.

give you the unexpected harvest

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Yeah people say “I have to go now” as a casual think like someone when their finished eating with their friends at a restaurant or something. :P ..Just tacking on to your answer :)

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