AnkitMaheshwari - 6:43 am on Jan 20, 2011 (gmt 0)

Check if your listing is as per Google Places Quality guidelines especially the Title of the listing. Also, an incomplete address can cause issues.
If you are using the Category feature, I would suggest try and pick from the options provided by Google in place of creating your own as this caused one of our listings to stay in pending state for a month. As soon as we changed to pre-populated category it got approved.