Out of all the "features" that anger me the most are automatic, silent upgrades. One can generally disable them but I dont want to have to figure out how; if I want an upgrade I will download and install it manually and do so when I am good and ready.
That web applications - as opposed to those I install locally - are increasingly common I regard as the problem not the solution. Quite commonly a website breaks for no apparent reason, eventually I clue into that they revised their Javascipt but did not test on the browser I actually use.
When considering whether to install software, first look for reviews. Many eCommerce sites make it easy to sort by most-critical first. Do take them with a grain of salt as bad reviews are sometimes posted by unethical competitors as well as cyberstalkers like Kuro5hin's modus.
If those bad reviews would affect you and are in a recent release then maybe you want to give it a pass.
I know all about security patches, I once got to play on that same Sun workstation that Kevin Mitnick ransacked but at least I had the sense to ask Tsutomu's permission first.