By way of the always interesting James Fallows, here's a site that lets you make your own maps of world temperature data since 1880.
This familiar projection of the world map shows that July has been getting warmer in the northern hemisphere over the last decade. Perhaps you might be less impressed by climate changes in winter if you live in Brazil or Argentina.
On the other hand, this polar projection of the same data shows very clearly that winter warming is significant on one side of Antarctica. No wonder chunks of ice shelf are falling into the sea.
Go play for yourself.