I use Swedish allot and I feel that I almost have the opposite problem. My english is getting worse and worse =P But that's probably because I've studied Swedish for 1,5 years at the university. So I've started to think about swedish allot.
I'm not worried about Sweden losing its native language. At least not at the moment According to a few studies swedish isn't in any danger in most areas. The only areas where swedish were threatened by english were in the natural sciences (like biology, physics and chemistry) and ecconomics where they hadn't translated most of the different terms and words they used in those areas into swedish. As long as swedish parents speak swedish to their children we won't lose our native language.
As for cultural identity. I think that allot of swedes believe themselves to be allot more international then they really are. We don't really feel allot of pride for our past, but most swedes feel pride in the country we have today. I'm pretty sure most swedes see sweden as a good role model for other countires to follow, even if it's not always considered "cool" to admit this (and bragging is generally frowned upon). Many of us are proud of our peacefulness, our neutrality, our socially just and free society and our effort to save the enviorment. And allot of swedes scratch their heads and wonder why other countries aren't like sweden. Don't they see how great we are? Are they insane? This pride has diminished alittle though since the welfare society that Sweden built during the 50's has started to be dismantled.
(and to answer the original question; no I don't think there will be a global language nor should there be).