Minutes, days, weeks, months, even years. Hopefully it will never be decades.
Since we are not a listing service, we don't look at the clock in terms of how long a suggested URL waits before we look at it, thus, it is truly imposible to predict. One might have better luck guessing how many individual snowflakes will land in within the boundaries of the City of Boston over the next 12 months.
If you have submitted your website, it is complete (no "coming soon" sections), it is rich in content of your own making (not copied from elsewhere and repackaged), you have gone through our guidelines and are reasonably confident that it is guidelines compliant, and finally, have submitted it to the single best category, then you have done all that you can do -- other that to wait patiently.
And, since we no longer give any confirmations other than the one that appears onscreen, we will allow you to resubmit once (and only once) about a year after your original submission (and you are sure to submit to the same category).
This second submission reduces the odds of a lost suggestion into a number that is comparible to the chances that I will be elected President of the US in the next election.