PostgresSQL 9.0 64 bit on windows 2008 64bit

Hi
We currently use postgres 8.3 on windows 2008 32bit
With max_connections set to 1000
Since we have more than 125 connections, we run postgres as a stand alone process instead of as a service.
http://wiki.postgresql.org/wiki/Running_&_Installing_PostgreSQL_On_Native_Windows#I_cannot_run_with_more_than_about_125_connections_at_once.2C_despite_having_capable_hardware

Now when we are upgrading to Windows 2008 64bit running PostgreSQL 9 64 bit.
Can we run it as a service even though we have max_connections set to 1000 or do we have to run it as a stand alone process?

Is there an upper max_connection that isn't good to pass, when running on windows,
Say that I would set max_connection to 5000 and then have 5000 postgres processes running on the server, is that wise?
Must each connection have to start a new process?

I guess we should look at pgBouncer (actually we have looked at it but it's not in use right now)

Thanks
/Niklas