Well watercooling is only necessary if you're looking for better overclocks or you just want better temps. I have it and I absolutely love it but its not necessary.
About the sockets, AMD and Intel don't usually change their sockets very often at all. I think AMD went through a few lately but thats the exception. LGA775 lasted a REALLY long time and 1366 will too. Sockets don't change very much, CPU technology does on the other hand. But if you were to get an i7 build, you would have the newest socket that will be around for years to come. The e8500, if clocked really high MIGHT outperform an i7 on some games but not by any noticeably amount so IMO, it is better to get an i7 that will perform very very well on games and amazing on every other program. The debates will eventually come as to whether to get i7 or the next best thing but that day isn't here and it will be a little while before it comes so why not get the i7 when it really isn't very expensive for the performance you're getting and you will be future ready with the new socket. Thats my 2 cents
point taken...
question... how much can they be OCed to? Ghz wise?