Perhaps the best indicator (yet) that Russia is considering some sort of military presence in Cuba. From Reuters:
Russian Prime Minister Vladimir Putin on Monday said it was time for Russia to rebuild links with former Cold War ally Cuba, news agencies reported.
The Kremlin is angry at U.S. plans for a missile defence system in Eastern Europe, and last month a news report suggested Russia might use Cuba, a thorn in America's side for half a century, as a refueling stop for nuclear-capable bombers.
The Russian Defense Ministry denied the report, and military leaders have made similar claims in the past.
But Mr. Putin is more than your ordinary Prime Minister. He is clearly the power behind the throne and if Putin thinks sending Russian bombers to Cuba is a good idea, there's a pretty good chance that Bears or Blackjacks will visit the island in the coming months.