It probably depends on the kind of account. I got approved instantly, but then already had adsense on websites elsewhere. The suggestion to wait a week is good. How long ago did you apply for adsense?
I always advise people to wait with monetizing till they have at least 100 visitors a day to their online property. If you're only using adsense on hubpages, don't apply till you have at least 100 visitors a day on all your hubs together. One reason this is a good idea is that the chance of being accused of click fraud is less. Another: you won't be making significant income early on anyhow. Better focus on getting links and traffic first. Money second.