From time to time various different players have connection issues between each other - it's frustrating - tonight I had it twice. (with Gizmo James and SirJJ575)
This is NOTHING to do with the game, or the F2 server backend - you can prove this by simply opening a chat message to the other gamer - and it will say 'connecting' - but never will.
The following is a cut n paste from the a 360 MS support page:
For example, you might want to host the latest Xbox Live title, and you verify that your router’s NAT type is “Open.” Using the table, you can know that your router’s NAT type will not prevent your friends (who may also be using a router) from finding your session, hearing your voice, and enjoying a great gaming experience.
Now I am a computer guy - I run an Open NAT (actually, anyone playing with me is DIRECTLY connecting to my 360, because I run my 360 on a Firewall which allows me to place a machine into a DMZ (so absolutely, 100%, no filtering - the firewall simply passes the data onto the 360 without any rules being applied)
I have been doing networking for years, I know that it's not my setup - Mine is Open, but the problem is that if someone is not open, you might have issues. (also some ISP's who provide the router for you update them silently so testing often is required)
I would like you to check what yours is set to - the best is OPEN.
If you don't know how to check - go to the dashboard, network settings, test xbox connection - run the test - the result will be shown at the bottom.
some stuff from MS :
http://support.microsoft.com/kb/908880/?sd=xbox
http://support.microsoft.com/kb/840420?sd=xbox
http://www.xbox.com/en-GB/support/xbox/connect/dashboard.htm
http://www.xbox.com/en-GB/support/xbox/connect/router/troubleshooting.htm
Network speed
A good test for us all - http://www.speedtest.net
Notice how yu can pick a server anywhere in the world to check yourself against. I would pick somewhere non local to all of us - maybe that single server in Lisbon, Portugal?
Mine was: 370 Kb/s download, 90 Kb/s upload
really bad like DSL 500
Of course it will vary for us all - but it does help to understand if that is your issue on the night.

