@clarknova:
I tried diagramming what you have described and it's pretty confusing. Mind you, I'm pretty novice.
One things stands out to me though, you have 2 switches, and yet you have opted to run LAN and WAN on both switches. If you want to review a thorough discussion on why this is bad, have a look at this recent thread on the mailing list:
http://marc.info/?l=pfsense-support&m=128098748819739&w=2
I've never used pfsync, so I won't comment on that, but I think the first thing to do would be to plug your internet connections and pfsense WAN ports into SW1. Plug your server NICs and pfsense LANs into SW2. Arrange your vlans the way you like and put your loop woes behind you.
For the LAN WAN issue on both switches I saw that issue too. I had bought 2 addition switches to handle the WAN connections and got rid of the VLAN problem. I ran into another problem though with WAN Failover not working right because the WANs were on the same subnet. So I ended up witha whole new solution:
I Got rid of the Dual WANs on each PF and just went with single WAN connctions on each. I plugged the independant WAN cables from the datacenter directly into each PF WAN port. I am just using the 2 Dell switches now and have the LANs of each PF going to different switches. All servers have 4 NICs that are loadbalanced, having 2 cables going to each switch for redundancy. This way I can loose a switch and everything will still work. I also set up carp between the PF's So I could loose a WAN and still get out and same with loosing a LAN. It seems this setup is alot cleaner and is working great. The 2 WAN lines coming from the datacenter are already running HSRP on their end.
Jon