Web Server and Exchange 07

Is it ok to run a web server and exchange 07 on the same server. Are there security or performance concerns to this option. I’m trying to limit the number of servers we run on our network.

We currently have approx. 100 users, 60 devices, on our LAN

Our current site that is hosted somewhere else recieves approx 2000 hits per month.

Still want room to grow on this system.

Any Suggestions?