Its back. I noticed it disappeared for about two weeks and my friends and I all though something was wrong with our phones! Im so glad they brought it back.
The real reason is, Verizon has done lot's of studies and there numbers show that 98% of text messages are delivered perfectly within 16 seconds... So it does make sense on there end (business wise) to take out the feature, but I also understand and feel why you think the feature is great and how stupid it is to remove the feature