SQL Server 2012 has a number of new T-SQL features.  Listed below are all of the new features, along with the best links I have found that describe each feature:

WITH RESULT SETS, OFFSET AND FETCH, THROW, SEQUENCE: See New T-SQL Features in SQL Server 2012 and SQL Server 2012-DENALI-whats new in T-SQL

FORCESEEK and FORCESCAN: See FORCESEEK and FORCESCAN – New enhancements with Table hints in SQL Server Denali CTP3

Conversion functions: See New Built-in Functions in SQL Server 2012 Denali and SQL Server 2012 – new conversion functions

• PARSE (Transact-SQL)
• TRY_CONVERT (Transact-SQL)
• TRY_PARSE (Transact-SQL)

Date and time functions: See New Date and Time Functions in SQL Server 2012

• DATEFROMPARTS (Transact-SQL)
• DATETIME2FROMPARTS (Transact-SQL)
• DATETIMEFROMPARTS (Transact-SQL)
• DATETIMEOFFSETFROMPARTS (Transact-SQL)
• EOMONTH (Transact-SQL)
• SMALLDATETIMEFROMPARTS (Transact-SQL)
• TIMEFROMPARTS (Transact-SQL)

Logical functions: See New Logical Functions in SQL Server 2012 (IIF and CHOOSE)

• CHOOSE (Transact-SQL)
• IIF (Transact-SQL)

String functions: See CONCAT() string function–SQL Server 2012 and SQL Server v.Next (Denali) : CTP3 T-SQL Enhancements : FORMAT()

• CONCAT (Transact-SQL)
• FORMAT (Transact-SQL)

Analytic functions: See The new Analytic functions in SQL Server 2012

• CUME_DIST (Transact-SQL)
• LAST_VALUE (Transact-SQL)
• PERCENTILE_DISC (Transact-SQL)
• FIRST_VALUE (Transact-SQL)
• LEAD (Transact-SQL)
• PERCENT_RANK (Transact-SQL)
• LAG (Transact-SQL)
• PERCENTILE_CONT (Transact-SQL)

More info:

Video The T-SQL Cookbook: What’s Cool in Microsoft SQL Server 2008 R2 and New in SQL Server Code-Named Denali”

Programmability Enhancements (Database Engine)