So with all this Global Warming, how many of the world's weather stations saw cooling over the 20th century?

A third:

As far as I remember, this is the first time when I could quantitatively calculate the actual local variability of the global warming rate. Just like I expected, it is huge - and comparable to some of my rougher estimates. Even though the global average yields an overall positive temperature trend - a warming - it is far from true that this warming trend appears everywhere.

In this sense, the warming recorded by the HadCRUT3 data is not global. Despite the fact that the average station records 77 years of the temperature history, 30% of the stations still manage to end up with a cooling trend. The warming at a given place is 0.75 plus minus 2.35 °C per century.

Emphasis mine.  And notice that the uncertainty in the warming rate is three times what the warming rate is.

Even if you imagine that the warming rate in the future will be 2 times faster than it was in the last 77 years (in average), it would still be true that in the next 40 years or so, i.e. by 2050, almost one third of the places on the globe will experience a cooling relatively to 2010 or 2011! So forget about the Age of Stupid doomsday scenario around 2055: it's more likely than not that more than 25% of places will actually be cooler in 2055 than in 2010.

We're always sneered at for missing the distinction between weather and climate.  Cooling experienced over 1500 weather stations over the course of 77 years seems to fall into the bucket of "climate".

You know, if the theory of Catastrophic Anthropogenic Global Warming were as solid as we're told, evidence supporting it would be falling off of the roof eaves and littering your driveway in the morning.