It was noted at the time that Nevada in 2008 was especially poised to swing against the incumbent GOP. This was cause Las Vegas was one of the Housing Crisis hotspots, and the Vegas metro decides Nevada elections. There is a argument then that even with the 2008 landslide, Obama was outperforming expected outcome.
While not as important, 2008 was when Washoe County flipped as GOP win it every election from 1968-2004 but since 2008 has gone Democrat every time. Reno being a smaller city likely reflects trend of those becoming somewhat more Democrat throughout country. Obama in 2008 also won Carson City, but has voted GOP in last three elections. I believe Washoe County has more college educated whites than Clark County so maybe partly why it flipped while Clark County only goes Democrat due to large non-white population and even then GOP does quite well considering its size and non-white population despite falling short.