I did an upgrade installation, and have Money 2006 installed on my machine. After the installation, everything continued to work. However, Money 2006 is slightly odd around the edges, as can be seen below:
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Instead of getting the glass edge to the window, I get a gray line. No problems for me though.
The next thing I ran into was how do I synchronize my Pocket PC with the system. The only reasons I ran into this were that my device wasn't detected, and when I did manage to get it detected, it wasn't that clear what to do. For the latter, I put a new article on the Money FAQ site at FAQ Article 447.
The former required me to download some beta drivers from the MS Downloads Site. These pre-release drivers should hopefully be replaced soon with some released ones, especially if people are going to start using Vista shortly.
And what do I think of Vista - well, the interface is very nice :-)