Fredrick Marckini’s “Ass-Backwards SEM” article at ClickZ makes some good points. Without an effective site focussed on meeting user goals (or more crassly “converting them”), optimizing search engine ads is tweaking when major work is still to be done.
Here’s a quote from the end of the article:
“Pursue a strategy for conversion enhancement first. Then you can double — or triple — your PPC search advertising campaign with great effectiveness. Anything else is inefficient and sloppy.”