ALL the time. If you haven't heard anyone talking about them, your friends must not read much.
Or maybe my friends just read abnormal amounts of books and comics... which isn't unlikely given my social circles.
Personal taste aside, I feel like the trend is downward for fans who came in back in the Mirage days. BUT the downward trend has upticks with each new resurgence of TMNT.
Give the cartoons long enough, and they get pretty bad. Fred Wolf, but I'm obviously a hater; 4Kids and Nick both lost their way as well... or, if you enjoyed the later seasons of both shows, you probably will admit that the shows radically changed the formula a couple of times to try to stay "fresh" with debatable effect.
When 4Kids was going well, we had Volume 4 and Tales Volume 2 going strong and a CGI movie. When Nick was going stronger, we had (still have!) IDW comics and a couple of movies. But when the toys stop selling, the entire franchise starts sliding downhill again.
Aside from an enterprising filmmaker doing a truly good film series with a more Mirage-esque tone, I don't think we're going to make any progress back up the hill with the next iteration.