Magento

The Magento Preview Version CE 1.6.0.0-rc2 is now available. 
Please note that this release is a preview version. It is not the final release. It is likely unstable and NOT recommended to be used in any production environment (more information about preview releases and the community edition release process can be found in this blog post).

This release is available for upgrade through the Connect Manager, by download or via SVN. Instructions for installation using the Connect Manager are below.

As this is a Release Candidate we highly encourage extension developers to update their extensions to be compatible with this release.

Some of the key new features in this release include:

• Minimum Advertised Price (MAP Pricing)
• Persistent Shopping Across Devices and Browsers
• Enhanced Order Payment Action for PayPal Express Checkout
• And much more...

To see a full list of features and fixed issues please visit our release notes page. Diff files are available here.

Please report all issues with this release in the bug tracker.

Instruction on upgrading from Magento 1.5.1.0 to this preview of 1.6 using the Connect Manager are as follows:

1. Open Magento Connect Manager by navigating to System > Magento Connect > Magento Connect Manager.
2. Enter your Username and Password that you use to log in to the Admin Panel
3. In Magento Connect Manager, click Check for Upgrades in the Manage Existing Extensions fieldset.
4. When the search for upgrades is complete, the “Upgrade to 1.5.1.0.1” will be listed in the Available column for the Mage_All_Latest package.
5. In the Actions column for the Mage_All_Latest package, select “Upgrade to 1.5.1.0.1” and click Commit Changes.
6. Make sure that package upgrades are successfully installed by viewing the console messages below.
7. Click the refresh button below the console window.
8. Go to the Settings tab at the top of the MCM window.
9. In the Preferred State drop-down field, select Beta.
10. Click Save Settings.
11. Go back to the Extensions tab.
12. In the Manage Existing Extensions fieldset, click Check for Upgrades.
13. In the Actions column for the Mage_All_Latest package, select “Upgrade to 1.6.0.0-rc2 (beta)” and click Commit Changes.
14. Make sure that package upgrades are successfully installed by viewing the console messages.
15. Click the refresh button below the console window.
16. Close the MCM window and refresh your frontend. Your system is now upgraded to version preview 1.6.0.0.

Note that if you recieve a Service Temporarily Unavailable page after refreshing the frontend, you will need to open the Magento installation directory on the server and remove the maintenance.flag file. Then go to Magento var directory and remove the cache directory.  This will take care of the issue.