Here is a tutorial for installing and using a newer Windows 7 network monitor called Netmon.
http://blogs.msdn.com/b/usbcoreblog/archive/2009/12/04/etw-in-the-windows-7-usb-core-stack.aspx
I haven't tried it to see if it works. When I do, I will post an update saying whether it works with Windows 7 x64.
EDIT:
It worked on my Parallels Win7 x64 Virtual Machine.
The biggest downside was the massive amount of packets it logged. To help with this, the following filter can extract only the packets with your USB VID (vendor id), where the vid is 0xABCD.
// Following searches frame for hex data of 0xAB 0xCD
ContainsBin(FrameData, hex, "AB CD")
Note: As in the tutorial, to log usb packets, use the following commands in a cmd prompt run as an administrator:
Logman start Usbtrace -p Microsoft-Windows-USB-USBPORT -o usbtrace.etl -ets -nb 128 640 -bs 128
Logman update Usbtrace -p Microsoft-Windows-USB-USBHUB -ets
//Perform desired usb activities
Logman stop Usbtrace -ets
EDIT 2
UsbSnoop is another free option. I have confirmed that it works on my Win7 x64 machine.
http://www.pcausa.com/Utilities/UsbSnoop/