You can check your application status onlinewww.myapplicationstatus.com/barclays
Barclays recon phone number - 866-408-4064. 8am - 5pm
Barclays is known to pull your credit again when reconsidering - even when specifically asked not to.
Make sure to explicitly tell the rep that you dont want another credit pull. The benefit of such action would be that if later you see they did pull your credit you can call up and speak to a manager and have the pulls removed (based on first-hand accounts from this thread).
If you want to guarantee that you don't get another pull, freeze your credit report.
While Barclays recon reps are usually very tough to deal with, there have been sporadic reports of them reconsidering by reallocating credit-line from other cards. Additionally, there are a few reports indicating success with the 3BM.
Barclays recon reps take notes of each phone call and subsequent reps usually regurgitate the previous rep's reply.