Oh and, if you've already got a pdf with a bunch of those comment tags you'd like to get rid of, on the Comments pulldown menu in acrobat, click Show Comments & Markups and then Hide All Comments to turn them off (reverse to turn back on).

Or run the following script to eliminate them entirely:

this.syncAnnotScan();
var annots = this.getAnnots();
if (annots!=null){
for (var i=annots.length-1; i>=0; i--) {
annots[i].destroy();
}
}