I downloaded windows 7 Beta build 7000 last week and installed it on a virtual box with 512MB of RAM and everything went smooth, the performance is so good just like XP, then i thought to try installing ESRI products on it, i started with ArcGIS Desktop 9.3, i went all right without any problems, infact i feel that performace wise it little faster then XP or Windows 2003, didn't run any performance analysis program but just felt it. here are some screen shots
| ArcMap 9.3 Installation |

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| ArcMap Up and Running |
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