We feel that if someone actually clicks through to those pages we have done our job.
For some obscure terms it can be as high as 50%.
For the general, high volume searches our conversions run around 30%. If we can keep it around there we are happy.
Another tip is don't worry about 1 day - have a look at say 7 days of numbers. If you are getting very poor results on one term and high on another try altering the ad to be more specific. Good Luck.