Nikon's upcoming entry-level D3100 DSLR is in Best Buy's inventory system with an expected ship date of September 18, which is about a month after an expected August 19 launch date. NikonRumors said today that the SKU listing indicates DSLR will be bundled with an 18-55mm zoom lens, though no other specifics were revealed by the leak. An official announcement from Nikon regarding the D3100 is expected for next week.