I spoke recently to Colin Keating, a former UN ambassador from New Zealand and head of Security Council Report, which keeps a close eye on that body. He pointed out something interesting: in 2011, the UN Security Council will likely include more major powers than at any time in recent memory. In addition to the five permanent members, the Council will have Brazil and Nigeria (current members whose terms expire at the end of 2011.) All but certain to be new members are India and South Africa. And depending on how the General Assembly votes this fall, Germany and Canada could both snag seats (they're in a three-way race for two seats with Portugal). In all, more than half the G-20 may be represented. It will be an interesting test run for how an altered Security Council might perform.
For the aspiring permanent members, Council membership will be a delicate dance. On the one hand, they'll want to show the broader UN membership (whose votes they need to get any Council reform plan through the General Assembly) that they can stand up to the permanent five on key issues. But too much freelancing may annoy the P5 and make them less amenable to adding new permanent seats (some diplomats I've spoken with believe that the Brazil/Turkey foray during the Iran sanctions debate may have already had this effect).