For example we have 360 GB LUN's for our Exchange Servers. We have EDB files that are approaching 300 GB's is there a point at which the databases will dismount or will they grow as large as the file system and dismount? We are running Exchange 2007 SP2 Enterprise Edition. Thanks!

The physical limit is 16TB or so (ese limit), so no, it will be disk and filesystem limits before ESE. Shaun

Note, that you shouldn't really have Mailbox databases of that size if you can help it. With 2007 the idea is to have multiple EDB's so that you can lessen the time for recovery etc. If you have 400GB of email data, and you run Enterprise edition, why not have 10 x 40GB EDB's. much easier in the event of database corruption. Shaun