I use batiks constantly and it's never actually entered my head to change anything to treat them any differently than I do using ordinary quilting fabric!
I choose my needle according to the thread I want to quilt with - for 50wt I usually use a 80/12 Quilting needle, for 40wt a 90/14 Quilting or Topstitch needle. For metallic thread I always use a Topstich 90/14 (or Metallic needle if I have any - essentially the same) and have just recently tried the Superior Titanium Topstitch (not quite sure yet if the extra expense is justified). Happy quilting!
