The problem with these uprisings, particularly in Ukraine and Venezuela, is that they're not fueled by food prices. I don't know the fine details about the Ukrainian case but I've been reading quite a lot about Venezuela. And I happen to live in Argentina so I see a lot of parallels between the Venezuelan case and the Argentinian (Venezuela is a little window to the future for us Argentinians).
Basically, Chavez got to power through a coup in the 90s. Since then, Venezuela has been going downhill. Like all "socialist" countries, Venezuela has failed to establish a solid industry, financial sector (obviously), and "free trade" concept. In Venezuela, like in Argentina, everything has to be approved by the government. Many private businesses close, and to keep the unrest, the government hires those people, to create idle "Ministries". Following Castro's example (and leadership, since Venezuela now is effectively governed from Havana), venezuela has armed militias "to defend the revolution" (the estimated number is 300.000). They openly acknowledge this fact and the militias themselves say they will defend the revolution "by any means". Their army is also co-opted by Communists, and the intelligence services by Cuban agents (according to Venezuelans they're easy to spot, as they don't have a venezuelan accent).
Venezuela has also jailed the opposition leader, accusing him to be a CIA mole, instigating protests.
Obviously a system like this can only be sustained by corruption at all levels. Venezuela's government managed to destroy PDVSA, the country's oil company, and because of this, they destroyed all their economy (since they're completely based in oil and never bothered to diversify, since Venezuela had so much of it, fuel was cheaper than bottled water). Elections were "tight", and the other candidate lost by 1.8%, amongst accusations of burned ballots.
What's happening now is simply that a good portion of the population sees the country becoming a satellite of Cuba. Chavez signed an agreement giving Castro 53.000 barrels of oil a day, a number that's since been increased. In exchange, Castro sends "doctors" to Venezuela (and among those, a good deal of intelligence agents to indoctrinate the population and forces). People protesting are simply demanding the corruption to stop. The government is answering to this violently, claiming this is all a coup orchestrated by the CIA. They're just trying to hold on to power by the force.
I see this happening in Argentina soon. The government is using all of Venezuela's tactics (a little more subtle, but essentially the same). Food prices are high but not unaffordable. People protesting aren't the poor, it's the "middle" classes. The 50% of the country that didn't vote for this government, and through taxes, they have to support all the people living off government subsidies or working for the government, while having no benefits for themselves (in Argentina, the government is sticking its hand up the retirement funds to pay for subsidies for the "poor", essentially pissing your future).
What I see in both cases (Venezuela and Ukraine) is that protests start normally but they're later turned violent by communist chaos agents (Cuba in the venezuelan case, and Russians in Ukraine). While I don't think Russia is looking to become communist again (since the country is now ruled by the rich that made their fortune after 1991), they still use the same tactics they used in the USSR era.