What is the difference between ALTER INDEX and DBCC DBREINDEX? Is the only difference between 

ALTER INDEX [index_name] on [object_name] REBUILD with (ONLINE=OFF, FILLFACTOR=90)


and

DBCC DBREINDEX([dbname], 90) 


just that the DBCC command will reindex all of the indexes on all of the tables in the database?
The DBCC command is a consistency checker utility inside of SQL Server whereas ALTER is a DDL SQL command.  The DBCC REINDEX command was deprecated in a previous version so it is not as robust as the new ALTER INDEX command is today.  There is more functionality in the ALTER INDEX than the DBCC REINDEX commands:

http://msdn.microsoft.com/en-us/library/ms188388.aspx

Happy indexing!