Thanks Ant1-b0dy (cool nick) and BlueSpot. I take back my expectancy of 64bit support, there are not many programs yet that have it, those which do (for example Firefox) are still for testing, since all the plugins don't work.
And yes, it was my enthusiastic decision to get XL 2011 - finally here! I want it! - without reading the small print on the side of the box for the specifications.
Still OK for those who qualify for upgrade price. Some of my friends who haven't seen SimCities before are fascinated with the idea of building a whole city and managing it. So I've temporarily lost control and access to my machine, and may have made a few sales, as some people, who are not into computer simulations, want this at their home computers!