Best 2nd Line Therapy for Diabetes treatment identified

It has always bugged me that while we know metformin is the best 1st line treatment for Type 2 Diabetes, there has been no clear consensus on what to add to metformin if the patient does not reach the A1c goal of <7%.
    Medscape.org had a nice article/CME activity showing GLP-1 treaments (Byetta, Victoza, Bydureon) should be preferred.

http://www.medscape.org/viewarticle/762095 :

• "A previous study by Dodd and colleagues found that most type 2 diabetes was managed with oral medications, and slightly more than half of patients had achieved good glycemic control. There was a shift in the most popular oral medications from sulfonylureas to thiazolidinediones during the study period from 1999 to 2004.
• GLP-1 analogues are recommended as second-line treatment of type 2 diabetes in the current study by Liu and colleagues based on their efficacy in reducing both A1C levels and body weight while presenting a low risk for hypoglycemia. "