I gave up trying to connect with other players yesterday and decided to play more in the "story" mode, unlocking chapters, etc. I'm happy to finally get a silver icon and I'm looking forward to getting better day by day (week by week).
The videos are so cool too
Edit: I was online tonight with my SPI firewall enabled and I was not able to join any sessions. So, if you are having problems joining sessions, check your router settings and be sure to disable the SPI firewall.