I'm noticing this more and more.
1) A little while back, I upgraded from a Gen 4 iPod photo to a iPod video. It's good. However - Apple, in their infinite wisdom decided to remove Firewire support. I had to buy a USB 2.0 card to use it. Annoying, especially as on their website Apple made out that it must have been magic that the new iPods were lighter and a little bit cheaper than their previous generation. Moreover, although the new iPods have a stopwatch (WHOHOO!!) the clickwheel is way too responsive compared to the last model. Now you have to fanny about going back and forth through menus because the slightest movement moves the cursor way too far ahead.
And the new thinner iPod also won't fit in my old wallet designed to hold the old fat bastard pods. So now I have to use that idiotic pouch that you can't even see though. What's the point of it?
2) This morning I opened up Winamp to listen to some brutal metal (natch) and there was a new version of Jump To File, the most useful and genius plug-in of them all. I downloaded it and was surprised to find no appreciable difference to the previous version - save for the fact that pressing Shift+Enter no longer enqueues a file while the dialogue is open. So essentially the 'upgrade' is just a useful feature removed.
3) Windows updates. I stopped allowing these many months ago. They never had an appreciable effect anyway, but at some point Microsoft thought it would be fun to just make them change the configuration of random components on your computer out of some misguided desire to help. This is why System Restore has become invaluable over the last year or so.
Why do companies do this? Haven't they heard of focus groups? I.e. Me?