title: NSMutableArray initWithCapacity nuances
body: <p>Does anyone have advice on how to best initialize an NSMutableArray when it comes to dictating the capacity?  The documentation mentions that "...even though you specify a size when you create an array, the specified size is regarded as a “hint”; the actual size of the array is still 0."  So...</p>
  
  <p>1) If I init with a greater capacity than I typically use, do I not have to worry about wasted memory?</p>
  
  <p>2) If I init with a capacity typically lower than what I use, do I have to worry about heavier processing time allocating more memory to hold the extra elements?</p>
  
  <p>Just how impacting is this initialized capacity to the performance/memory usage of this data type?</p>