I mostly disagree. Sure, I've been frustrated at times when I can't express an idea in 140 characters, but in general, I think the limitation is a benefit. As a creator, it makes me distill my tweet to the purest essence of what I'm trying to say, and as a consumer, it lets me scan through my timeline quickly.
Also, there's nothing stopping people from tweeting an idea and including a link to a blog/gist/whatever where they add more context.
And if Twitter does expand the limit, I hope they do it in a way that is essentially a structured version of a link to something else. For example, keep the 140 character limit, but also let people attach a longer note – up to, say, 5000 characters, maybe with simple Markdown formatting. Support it in all official clients and give 3rd-party clients a way to support it too.
I have no problem with them expanding the limit as long as I can still scroll through my timeline, seeing 140-max tweets with an option to click on one to see the expanded version, without leaving my Twitter client or loading a whole webpage. A worse option would be to just show the first 140 characters of a longer note. I think there's value in forcing people to be concise, but I also get that there's value in letting people post longer messages and keeping all of that content in-network.
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