jTDS is the fastest JDBC driver for Microsoft SQL Server. The 0.7 release comes with a huge number of new features, implementing pretty much everything in the JDBC 2.1 spec and even some 3.0 features. A lot of work has gone into this release and this can be easily seen by looking at the size of the change log.
Also, just before the release, jTDS was tested against a number of test suites, including the performance tests provided by commercial driver vendors and the Hibernate test suite. These have shown (again) that jTDS is the fastest driver in many tests and really close in the others. The results will be made public soon (excluding the JSQLConnect driver, whose license prohibits this) on the jTDS site.
o Full support for scrollable and/or updateable ResultSets.
o Batch update support.
o Full Blob/Clob support.
o Retrieval of generated keys.
o ConnectionPoolDataSource implementation.
o Complete JDBC escape handling.
o Added the "lastUpdateCount" parameter to control whether only the last update count is returned by executeUpdate() (to ignore update counts returned by triggers).
The number of bugfixes in this release is so huge that it would take quite an effort to list them here. Please consult the change log if you are interested in specific issues.