"An EU --- American Cold War?"
Would never happen...
"A Pan-African Union?"
It's possible considering the African Union plans on adopting a single currency by 2025 (though I doubt it will be in full use by 2030). With nations like Nigeria, Ghana, South Africa, Egypt, Kenya, Tanzania, Botswana, et cetera having stability and reasonable/pretty high growth rates I can picture Africa, the last continent on Earth to start development, as one of the possible global hotspots around that time. Still, it could be a risky topic to talk about.
"Islam Illegalized in several Europeon countries?"
That would go against the EU ruling that people are able to freely practice any religion they desire. It would be difficult for this to actually get approved by the EU without it hearing massive backlash from other nations, and possibly from the potential EU member Turkey, but with Europe's onslaught of muslims and the slow growing native population no one said it's impossible.
"A Christian majority"
More like a muslim majority.
"Turkey as a Great Power?"
Actually Turkey is a rapidly developing country and already apart of the G20. By 2030 I could definitely see them being a serious contender in global politics. I read a story on Businessweek yesterday talking about how Turkey may be the next Germany (http://www.businessweek.com/magazine/content/10_17/b4175044791242.htm ) . Still, I think a great geopolitical backdrop would be say Turkey entering the European Union during this decade. The reason being Europe's slow economic growth and negative population growth is dimming its influence in world affairs, so the EU admits Turkey in. Within a few years Turkey dethrones Germany as largest population in the EU, and then the trouble starts w/ the knowing a muslim nation now has the greatest influence over most of Europe. That, or maybe the story can be on the waging battle between pro and anit-turkey nations within the EU that oppose or welcome Turkey joining; possibly causes a rift between the nations?
"Rise of an Authortarian Indian regime?"
I don't see it happening, but hey no one ever said it's impossible.
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If you don't mind, I have a few ideas:
Cold war between US & China (basically US & NATO allies vs. China & it's SCO allies).
Rise of the North American Union
A islam/christianity war emerging in Africa (this Yahoo article would be a good reference: http://news.yahoo.com/s/afp/20100415/ts_alt_afp/africausreligionislamchristian )..
Overall you have some pretty good ideas!