CTP2 can be downloaded at http://technet.microsoft.com/en-US/evalcenter/dn205290.aspx

Highlights in this release are

1. Report Builder and Power Pivot  is now available in different languages

2. .Differential backup on a database with in-memory tables backs up all data/delta files ie.data is not just differential. This means if in-memory tables are comprised of a significant portion of database size, differential backup will not be that useful

Try out CTP2. Please do share your experiences on the usage