One of my favourite books series currently is Ice & Fire by George R.R. Martin. Due to like many other fans waiting on the upcoming book in this series I check his blog from time to time for news. George Martin, like a lot of other people today is quite active online and thus interact with his fans through his blog and through email. In some way he is as available to the readers of his books as an open source developer is to the users of his or her software. And it is not always fun as George recently pointed out. As it turns out George experience is in no way unique and another writer, Patrick Rothfuss, did the following hillarious cartoon for his blog, which explains exactly how it these things feels for the author.
I think a lot of open source developers can recognize some of the stuff in those cartoons, the internet seems to be one of the best methods humanity has ever created for spreading negative energy around quickly and easily. So while less people bother emailing or blogging or commenting on a forum about their favourite open source tool compared to best selling books, the effect tend to be the same. The barrage of negative feedback drains the developer of energy and instead of encouraging him or her to bring out a new version to fix issues, in fact such feedback cause the developer to do less than they otherwise would.
I guess open source developers tend to be quite hard skinned in general, but I do remember for instance Arlo Rose, the guy who did the original graphics for Nautilus back in the day, saying he stopped being involved with the Linux community partly due to all the negative comments he saw on footnotes.
So a word for the road, if you want to achieve something in terms of dealing with anyone, be it the author of your favourite book or your favourite piece of software, your chance of doing that is much much higher if you stay positive.