Thanks for everyone's replies! It's a shame there is still no solid answer to the question. Seems like everyone had a different approach which I find very interesting.
I think we'll probably go with my gut instinct and shoot for waiting for solids till he turns 1. I have the luxury to breastfeed my son as often and as much as he wants since I don't work.... I have read up on iron and concluded there is no concern. Besides, if we get worried, we can just get his iron levels checked and make appropriate changes.
I am a little surprised that so many of you think introducing grains first is ok. I think bananas, avocados, squash and the like are much more appropriate as first foods. I would hold back even on rice for an extra few months just to be on the safe side. But that's just me... I think the whole "feed-your-kid-rice-cereal-at-4-months" thing is an American thing. None of my European friends or relatives ever heard of it...