What is getting annoying during last few years is the Co-Installations a lot of (typically free) software uses. I’m am in particulary annoyed when it is opt-out instllation so if you just click through in default install you get software installed and if software which is installed has little to do with software being installed.
It is my expectation as a “user” the vendor has picked the default installation options to really provide configuration what most user wants and getting in some junk in there hurts my trust to the vendor.
One very annoying example I have to deal with comes from Sun Java. If you install Java it will trypically check for updates automatically and suggest you to install them. When you install updates it will try to sneek in Yahoo Toolbar Each time ! With updates every couple of months it is only matter of time when somebody like me forgets to uncheck the checkbox and get the unwanted crap installed. I surely did it more than once and had to clean it up with uninstall.
This stratregy probably works well recruiting Yahoo Toolbar users and may pay off in terms of number of users to Yahoo and Sun. Many computer users probably would not notice and would not mind – and I guess this is what the marketing in this case count for. Some other people (like me) get annoyed and loose their trust to Yahoo for getting in such spammy software distribution tactics and Sun for making it possible.