Order of maintenance plan tasks
There is no point in updating your statistics if you are rebuilding your indexes. The statistics for an index are updated if the index is rebuilt.

Another problem is that the rebuild index job in the Microsoft maintenance plans are not intelligent so they just rebuild all indexes whether they need it or not. Brent Ozar talks about this here http://www.brentozar.com/archive/2012/08/sql-server-index-fragmentation/

The best solution for index maintenance is to schedule a custom script that checks for things like fragmentation levels and then performs the appropriate action. The best script out there to do this can be found here http://ola.hallengren.com/

If you want to stick with the native maintenance plans then I would just drop the update statistics job.