From the discussions I have had with student pharmacists, it seems that letters of recommendation are often overlooked, or are considered only at the later stages of the application process. There is recent literature related to residency applications in particular that highlights the importance of these documents. Many programs place a very high value on them. While you will not personally be in charge of this particular application piece, there is much you can do now to ensure those letters of recommendation are written favorably and complement your application.