Thanks all you guys for your replies so far, but I must admit to being very green when it comes to sound.

Can you answer this for me. If I just wanted to improve the audio at a wedding, say the ceremony, can you place a mike on a stand, and if so what sort of distance away from the bride and groom? At what distance does the microphone on the stand become no better than the on camera microphone? Also, would a camera mounted microphone, i.e. Sennheiser MKE-300, Rode Stereo Mic, Rode NTG-1 etc improve audio considerably over an on board mic?

Thanks in advance for anybody answering these queries.

Rob