I think Berlin would be a better choice as capital of the EU
With its history of division, its central location in the EU with the accession of the new member states and the many construction projects in the city, I believe Berlin would be perfect. Brussels is really too small and will lose its central location when the new Eastern members join the Union in 2004.
Well about 3 years ago I read that Berlin and Germany would eventually become the centre (physically and politically) of EU. Because of its position, economy and population. I think it makes sense and can only be a good thing.
Interesting idea, but as others have mentioned, I don't think many other countries would like the idea of Berlin as the capital. And I don't think it would just be the "major" countries like France that would protest (although they would). The smaller countries would probably look to that as further proof that they are going to be dominated by the larger countries. I think that's why the capital is currently in a "safer" place like Belgium.
Also, vaiva, Germany's economy is currently ailing (as are the economies of many other countries in the region, not to mention Japan and other nations) but Germany is still the economic powerhouse of Europe. In fact, last I checked Germany had the world's 3rd largest economy and even outperformed the US and Japan in certain areas.