This tirade was originally posted as a comment on this post on Google Plus; but given the content, it seemed like it would be wrong not to post it here as well.
[Edited to add]To be clear, I'm not accusing Google, or anyone at Google, from intentionally trying to kill the web. I know that most Googlers, and Google itself, strongly believe that an open interweb is a good thing. I'm fairly sure, although I don't know anyone involved, that the people working on Plus have good intentions about making it open; and probably believe that their custom API is better than an RSS/Atom feed because it offers more functionality.
I'm only commenting here on what I see as the net effect of Google+, as it is today, on the interwebs.[/EDITED]
Plus is killing the web because even Facebook offers more ways to track and be notified about that content than Plus does. Plus doesn't export any RSS/Atom feeds. The only way to pull data out is a custom API that nothing much supports yet - I can't even follow Google Plus from within Google Reader! I can follow my Facebook activity from within Google Reader - it's a limited feed that doesn't give me all the information I see within Facebook, but it's enough that I know I haven't missed any interesting activity from my friends. Plus makes it almost impossible to see anything but the last few posts, so I know that the interesting people I'm following are posting stuff that I'm missing. Stuff that if they posted to some open platform - their blog, twitter, hell, even Facebook - I'd be able to catch thanks to use of standards like RSS.
Plus is killing the web by tricking people into putting interesting content here that they would otherwise have put on their blog; then making it hard for me to find that content. For a while I'd considered "blogging" here (not that I blog much); but now that I've realised that posting here makes it next-to-impossible for anyone to find my content later, I won't be. My second thought was to have my Wordpress use the limited API to pull the content here into a post on my blog, but everything I've found that does that is ugly (and no, I'm not going to waste my time developing something when I could just post on my blog, on the open internet, and avoid the problem).
Plus is killing the web because it's driving comments here, for much the same reason as the above. It's easy for me to track down a comment someone made on +Robert Collins blog post about dmraid six months ago; if it was a post here, that would be impossible to find the post, let alone the comment.
Worst of all, by intermingling "Blog post" and "Link blog" type traffic (via the recent changes to gReader, amongst other things), Plus is killing the web by intermingling shallow commentary on half-read web trash (the kind of thing that used to be safely contained in gReader, delicious, or other linkblog type things) with interesting new content. Two-thirds of the reason why it would be impossible to find a six-month old post +Robert Collins had made would be the 7500 bits of crap in his stream since then - "Esconced for the wait until the flight", "Checked in in some random hotel in eastern europe", "aieee" being paraphrases of 3 of his 4 most recent posts. Blogs are for blogging; linkblogs are for sharing potentially interesting content, Plus is for dumping all your shit in and flushing.
In summary: Plus makes it harder to extract content than even Facebook; Plus encourages intermingling of the banal and the profound; and thus Plus makes it impossible to not miss quality content that would be found if it were posted on the open internet.
I hate to harp on about how Friendfeed got this right, but it really did. Friendfeed, although it aggregated my Twitter and my Blog, kept their identities as seperate streams. Friendfeed allowed you to choose if you wanted to see my tweets, my blog posts, or both. Friendfeed re-exported the stream I was watching as a single integrated RSS feed that I could then track in an RSS reader of my choice to make sure I didn't miss any content. Friendfeed made it easy to re-share posts onto other services such as Digg or delicio.us. Friendfeed made it easy to pull the comments made on an item inside Friendfeed back into the source, so that the conversation did not get splintered or lost.
I miss Friendfeed. I wish Google had managed to bring +Paul Buchheit and the rest of the team back into the fold - Friendfeed would have made such a fantastic open platform on which to build a social network.