"Conversion":: Its can be a great word and terrible. In my experience most of the conversion is from an 'Australian' Culture to the 'Church' culture. That people are not saved from their situation by Jesus but the Church culture which they are brought into.
"Saved" Again we have to ask what are we saving people from?
Types of conversion::
I can remember again a long conversation I had with a atheist work college who made the point that Christianity only converted those who where at emotional breaking point though their situations be it family breakdown, financial, addictions what ever. When people are in this situation they usually grab at anything.
Now days their are a lot more options (Counselling, anti-depressants etc) than just the Church for these situations. People usually go for the church when all of the options have been used up.
Occasionally you see it. A person has an intellectual curiosity which is a burning passion. They check out a lot of faiths or through a process of deduction and intellect come to faith.
I've seen it once or twice. Yet never to the extent of evangelical/fundamental faith. Usually their are degrees. From an atheist to a belief in God. Or from an Atheist to a follower of Jesus without the miraculous.
I'd put myself in this category. Interestingly the fragile and intellectual conversion if genuine will eventually come to the place of 'just know'. As much as you don't want to believe you can't help yourself.