Hate to burst anyone's bubble, but the Sprint Nexus S 4G won't be shipping from Best Buy on April 6. Over the past couple of days you might have seen the "Pure Google" phone switch to "Coming soon" on Best Buy's site, with a target shipping date of April 1-5, or April 6, depending on who you asked. Doesn't really matter, because it's all wrong.
First off, the dates have been removed from Best Buy's website. Secondly, we asked Best Buy, which quickly told us indeed it was in error, and that it's not shipping today, or tomorrow, or April 6. "We don't have a date yet," Best Buy tells us. (Oh, and then there's that whole thing about reps getting some Nexus S 4G training starting April 18.)
So don't look for the Nexus S 4G before Thursday, at least, and more than likely another for couple weeks after that.