G7's changing role in a changed world

In response to Crimea's parliament voting to join Russia and a referendum that endorsed the decision, the G7 leaders threatened to sanction Russia and boycott the planned G8 Summit in Sochi. However, Russian President Vladimir Putin's response was very calm and composed, saying "if they don't want to come, they don't need to".

Later on the G7 leaders held an emergency meeting at The Hague on the sidelines of the Third Nuclear Security Summit, claiming they will hold a G7 meeting in Brussels instead of attending the G8 meeting in Sochi and temporarily suspend their participation in the G8. Russian Foreign Minister Sergei Lavrov played down the G8 snub, saying "if our Western partners think that this format (the G8) has outlived itself, then so be it".

The verbal battle between the G7 and Russia and the G7's scaling up of sanctions against Russia give food for thought about the role and status of the G7 in today's international arena. How much attractiveness does the G7 still have for Russia? And how much will Russia suffer if it is permanently expelled from the G8?