Denton,
I would also recommend short and sweet, as Andrew and others have suggested. At my own wedding, we ended up having two receptions because we had family on two different continents. At my wife's family reception, my father-in-law toasted us with a glass of water (which I thought was respectful of my family's teetotalism) and tied in the purity of water to the purity of Christ and purity in marriage. Probably two or three minutes in total - worked very well.
At my family-hosted reception, my family's (fundamentalist) minister did a toast (as my father is dead) but his lasted 15 minutes+ and was basically like a sermon he would preach any Sunday, with full hell-fire damnation and mention of a young man who had died earlier that day in a car crash (with lines like, "Who knows where he is going to spend eternity; do you know where you are going to spend it if you died in a crash going home from this reception?" and so on). This was followed by similar 15-20 minute "toasts" by two uncles - so, as you can imagine, that reception was a bundle of laughs!
There's a time and place for the sermons and I don't think the wedding toast is the place. Hopefully the minister will have done a decent enough job in his 15-20 minutes talk at the actual marriage ceremony.
