From Microsoft, SSDT is now available for SQL Server 2014:

We’d like to announce the availability of SSDT that supports SQL Server 2014 databases.  SQL Server Data Tools for SQL Server 2014 CTP2 is pre-release software, does not support upgrade from an existing SSDT install or upgrading to any new versions of SSDT to be released, and should be installed only on a clean machine.  This toolset should not be used against production SQL Server databases.

We have started implementing support for new SQL Server 2014 objects, but we have a few known issues:

• Modifying a Memory Optimized table will drop and recreate the table during deployment without moving data.  This could result in data loss.  We suggest moving data to a temporary table before deploying changes through SSDT.
• There are instances where running Extended TSQL verification will cause Visual Studio to close when publishing a database project.  We recommend turning off the Extended TSQL verification option in the database project properties.
• Default constraints on a Memory Optimized table are not recognized by SSDT when working in the SQL Server object browser or initially publishing a project.  If you have them in your project and do additional publish, SSDT will try to alter the table to add the default constraint which is not supported on memory optimized tables.
• The table designer design pane will not support all new properties.  Users can work around this by typing the syntax into the script pane.
• The data compression option on clustered column store indexes is not supported.

We appreciate all feedback and encourage use of our forum or Microsoft Connect site. We would especially appreciate any feedback on the use of our tools against SQL14 databases and the new features.  If there is anything that is not working as expected or producing incorrect results, please let us know so we can address high priority issues before RTM.

Run or download SSDTSetup.exe from http://www.microsoft.com/en-us/download/details.aspx?id=40850.  We will not be providing ISO images for this release.  Alternatively, you can create an administrative install using the instructions on the download page.

SQL Server 2014 CTP2 only supports the following languages:  English, German, Japanese, Spanish, and Chinese (Traditional).