At about 20:35, Lexi's hair is clearly still dark brown under her scrub cap, when in this episode she is supposed to have dyed her hair blonde.
When Alex Karev hands Meredith Grey $50 to settle a bet, a flyer promoting Seattle Grace Hospital's Fall 2005 Flu Shot Schedule is visible on the bulletin board behind his head. While the series launched in 2005, this episode takes place in February 2010.