Nobody knows for sure what updates Google (GOOG) has planned for its Nexus 7 tablet. It’s rumored that a 32GB model will replace the 16GB model without a price hike, a $99 model will be released and a 3G model will also debut before the end of the year. is now reporting that it has a leaked listing for the 3G-equipped Nexus 7 that shows specs pointing to GSM and WCDMA connectivity. The site believes that Google will only release a 3G Nexus 7 with 32GB of internal storage, and that there will be no 16GB model with 3G.