SQL Server 2000 stores the full-Text index outside the database.  SQL Server 2005 stores the full-text index inside the database.  This means that when a SQL Server 2005 database is restored, the full-text index is also restored, with no rebuilding required.

The speed of building the full-text index was also improved.  A full-text index on SQL Server 2000 was taking up to 2 hours to build on a production server.  I restored the database to a laptop running SQL Server 2005 (upgrading the database in the process), and the full-text index built in around 6 minutes.

The use of the full-text index resulted in faster calls to the database.  Without the full-text index, the response times were 10 - 100 times greater (your results may vary).

I agree with the author's suggestion that there is extra overhead and learning involved with a full-text index, but the results can make it worthwhile.