I don't think anyone expects the West to intervene militarily regardless of what happens. Obama has bluntly warned Putin, but what can Putin expect if he props up Yanukovych in Crimea? My guess is that Putin will back down after he gets something for doing so. A civil war in Ukraine would not be good for Russia.
It's tough to say. Checking the demographics of Ukraine, with the western half being so pro-EU, maybe he's just taking the initiative and securing what territory he can. It's obvious that the Western half of Ukraine will not be accepting Russian rule, but the eastern half seems decidedly pro-Russia, and that includes Crimea. I doubt those on the Western side will ever be organized enough to take territory from the Russian military, and with no western intervention there's nothing really stopping Putin from keeping what he's taken.
It's possible. I can't say that I understand the place very well. Perhaps it could be a replay of South Ossetia. However, I wonder if Eastern Ukrainians would want Yanukovych, or if they would prefer Russian rule over keeping with the Western half of the country.
Well, regardless of anything else it's important they keep their influence in the black sea, so at the very least they -need- Crimea to keep access to their port in Sevastopol, as I don't think the new Ukrainian government would allow them anywhere near it following a withdrawal at this point. Because of this, territorial claims are definitely part of what they're looking for. Possibly in the form of an independent Crimea ala South Ossetia, or what seems more likely at this point full integration of Crimea into the Russian federation. I say this is more likely as Crimea already voted for independence before Russia stormed in and took their parliament over, soo... yeah.
I must admit I am not well versed on what's going on, so many different world conflicts at the minute.
So as I understand it Ukraine has been unstable for a while and the country has decended into civil war and the president/primeminister has been ousted.
Now is Russia seeing its chance to claim land on a weakened state or are they simply reorganising their current military bases located in Ukraine to protect their interests. Basically is this a power grab? I hate how little I can keep abreast of world politics, I am trying now though..
It's an incredibly complex situation with it's modern history dating as far back as the Bolshevik Revolution and a major player being the exchange of Crimea from the USSR to Ukraine in 1954 by Khrushchev. Ukraine hasn't had a stable government since the dissolution of the USSR and Yanukovych was seen as corrupt/a Russian puppet by pro-Western and EU Ukrainians. I wouldn't say it descended in to Civil War, there was no militant uprising that resulted in the new government though there was a bit of violence and conflict in the protests leading up to the sacking of the government. At the same time you can find evidence of Turkish and other Western involvement that has resulted in current situation and I'm still not sure what to make of that. It could definitely be seen as a power grab by Putin. Crimea has historically been pro-Russian and some Crimeans feel as though they were given away to Ukraine without their consent. Putin might be looking to claiming the territory, or at least allowing for a semi-autonomous state to exist there. The latter might inspire the rest of Eastern Ukraine to follow suit, which would cripple the remainder of the country as the economic centers are largely in the East. This is pretty reminiscent of the Georgian conflict and South Ossetia, as mk and amranu have already mentioned.