Here are some release dates that were leaked today:

July 12 – Frogger
July 19 – Cloning Clyde
July 26 – Galaga
August 2 – Street Fighter II Hyper Fighting
August 9 – Pac-Man

This info has already been pulled:

“Microsoft Confirms ‘Xbox Live Arcade Wednesdays’
[EDITOR’S NOTE: Microsoft has asked us to remove this press release, which was erroneously sent to news outlets by them before actually intended.

We have complied, but will re-post the information as soon as it is officially released. We thank you for your understanding.] ”

Source

From an Ubisoft Community Manager:

“With the release of Chapter 2 for GRAW, we also released a small Title Update that addressed some network connectivity issues. Additionally, we are working on a follow up Title Update that will address further issues, including ranked games problems, controller options, and some fixes. We are also planning on adding new Achievements for GRAW for players to obtain.

Details on this update will be released when the information is finalized.”

Source

Thanks FTC759 for the heads up.