Anyone who can't explain how they at one side have no problem believing in evolution which took us from non-biological material into biological creatures who can think and create computers, but somehow have a problem believing evolution could continue via technology I have no interest listening to.
The reality is we don't know what happens but we do know that we are seeing more and more complexity in technology which via ex. the internet is following it's own network effects and is showing increasing capabilities of intelligent behavior.
Whether machines will be self-aware and push us toward the singularity or this increasing intelligence just become a danger by it's sheer computational power is mostly academic.
The fact is that the Singularity _can_ happen and we would be wise to think about how to deal with this.