The Nexus One is Google, that's safe to say right? Wrong! Google has been denied the Nexus One trademark (of which they applied back in December) because of the "likelihood of confusion" with an existing trademark of the word 'Nexus' registered by Integra Telecom (who?) in 2008. Though we're not sure exactly how the process of trademarks work, we imagine whoever yells first (er, applies) gets the trademark. Score one to you Integra Telecom.
So though the Nexus One will soon be available on all four major US carriers--T-Mobile, AT&T, Verizon, & Sprint--it won't be a trademarked brand for Google. Yet. But because Google has deep pockets and Google typically gets what Google wants, we'd imagine Integra Telecom and Google will find a way to settle this. And probably for money. Score hundreds of thousands to you Integra Telecom.