Well that airbase where the "first shot" was given, it seems that the Ukrainian men wanted their jobs back, and are now cooperating with the Russians.
As for the defection
BBC News - New head of Ukraine's navy defects in Crimea
I dont know what information is coming to American news viewers, but I suspect it is rather selective when it comes to what is actually happening and very pro Kiev and anti Russian.. that is the usual bull**** coming from American media. Now I despise Putin but the real question is would you rather have the devil you know, than the devil you dont? On that front Putin and Russia do have a point.. there some elements of the Ukranian opposition that are not exactly kosher (yes that is a pun since they are anti-semitc racists).
Fact is the situation on Crimea is hardly black and white. You have the new government in Kiev trying to assert its power over a part of Ukraine that has a lot of self determination. The same people that are in the new government tried not long ago to curb this self determination and that has resulted in some of (if not a majority) the local police, para-military and other security forces to jump ship and pledge intelligence to the Russian back locally elected parliament and Prime Minister. Hell there is a story that some of these forces were actually dismissed by the people in Kiev and are now demanding their jobs back.. see the airbase incident.
It is basically a huge mess, and the fire is being fanned from all sides including the US and the US right wing. Some commentators here in Europe are pointing out that the rhetoric coming from Washington is more designed for the domestic politics that actual real world politics, since the US has very little trade with Russia in the first place and any sanctions or visa restrictions would probably hurt the US more than Russia.