Users with household income above $75,000 Facebook -- 41.74 percent MySpace -- 32.38 percent LinkedIn -- 58.35 percent Twitter -- 43.34 percent Users with household income under $50,000 Facebook -- 28.42 percent MySpace -- 37.13 percent LinkedIn -- 17.34 percent Twitter -- 28.36 percent Female users Facebook -- 56.33 percent MySpace -- 56.69 percent LinkedIn -- 48.11percent Twitter -- 53.59 percent Users aged 18 to 24 Facebook -- 10.27 percent MySpace -- 15.46 percent LinkedIn -- 3.99 percent Twitter -- 9.51percent Users aged 35 to 49 Facebook -- 31.54 percent MySpace -- 29.09 percent LinkedIn -- 43.64 percent Twitter -- 34.02 percent Source: The Nielsen Co. Do you trust these numbers?So what do we make of them?