I've often thought of posting threads like this but always stop myself - there are too many fanboys on these forums that blindly think Microsoft can do no wrong. I love my 920, Surface, Windows 8.1 desktop, and Xbox 360... but I agree with the OP, MS always seems to be playing catchup.
For instance, I'm as excited about WP 8.1 as anyone else. It's looking to be an enormous update. But it makes me realize how lackluster an update WP8 was. Cortana will come out 2 YEARS after Google Now, and even longer after Siri. Notification center has been in Android forever, and even Apple adopted it 2 and a half years ago.
Now we're heading into the era of wearable devices, and look at all the great press Google gets for their Android Wear initiative. Wouldn't it be nice if Microsoft were the one to introduce the world to wearbles on a wide scale? Even services like Xbox Music... nobody has any idea that they exist. Which, by the way, makes no sense considering they're trying to be a devices and services company. They should be advertising these things like crazy. I saw these short and sweet ads playing after the Superbowl for Google Play music, and books, and video. I have literally never seen a commercial for any of Microsoft's entertainment services.
None of this is to say MS makes crappy products and has crappy services - they're for the most part really good. The trouble is that the competition is also really good, and MS is NEVER the one to lead the charge.