Well, after all the interesting things encountered along the way of testing the cluster upgrade, the actual upgrade itself went quite smoothly and gave me no errors. I also applied SQL Server 2005 SP1 to the servers, and it updated both servers in the cluster, which saved me some time.
I went into Configuration Manager afterward to change the service accounts to a least-privileged user and noticed that the Integration Services service was NOT running on the virtual server, but on the physical server. A quick Google search to
http://www.sql-server-performance.com/forum/topic.asp?TOPIC_ID=11522 confirmed this.
I changed the service accounts to the non-admin user and restarted the server and it's performing quite well.
Wish me luck tomorrow - I'm running the Derby Festival Marathon in Louisville, Kentucky. (We get to run on the infield at Churchill Downs between the 8 and 9 mile mark!)
Derby Festival Marathon
Allen
P.S. One of the BI developers in my office pointed me to these links, which explain how to set up SSIS as a clustered service:
How to: Configure Integration Services on a Cluster
Making SSIS a Clustered Service
Thanks, Mike!