In previous articles i explained sqlserver 2008 concepts like Delete duplicate rows/columns from table,
Sql server 2012:
1.The SQL Server 2012 uses 48 bit precision for spatial
2.In SQL server 2012 has unlimited concurrent connections
3.By default it supports 15,000 partitions
4.Available new string functions CONCATE and FORMAT
5.Available new conversion  functions are PARSE ,TRY_CONVERT,TRY_PARSE
6.Microsoft.SqlServer.Dac and Microsoft.SqlServer.Dac.Extensions are introduced to perform  operations on Packages

Sql server 2008:
1.Maximum number concurrent connections to SQL Server 2008 is 32767
2.The SQL Server 2008 uses 27 bit precision for spatial
3.It can support only 1000 partitions
4.The CONCATE and FORMAT not available
5.Not available conversion function which are mentioned in SQL 2012