Ah yes, the 2011-2012 non-winter.
The jet stream varies in latitude. This year it happens to be a long way north in the western hemisphere, trapping cold air up by the poles and allowing warm air to flow north into the United States and southern Canada.
The cold air that should be giving us winter is then being pushed east by the jet stream and dumped on the poor people in Eastern Europe and Russia...they're getting their winter *AND* ours.
Not global warming, just an odd combination of conditions resulting in an unusually mild winter. This has happened before and will happen again...and the reverse could also happen, giving Europe and Russia a really mild/warm winter and us a horribly cold one.