My priest is 58 going on 59 and I was wondering which faction would be the best for me.  He's a 15/34/0 holy priest.  Thanks.

The primary difference between Aldor and Scryer is the Shoulder Enchants.  IMO, the Shoulder Enchants for Aldor are much better, particularly for Healers.  OTOH, you may also want to take into consideration your professions.  There are links to the differences in quest rewards, inscriptions, and recipes within the article below.

http://www.wowwiki.com/Comparison_of_Aldor_and_Scryer_rewards

Thanks for the link it helped a lot!