Lets all panic as a free social media service like @twitter makes a little change ...
Should I panic as some of my research focusses on the timed outputs of pedagogical content based around a microlearning model. Twitter lends itself to this, yet as is the case with mass broadcast social media ... unless you personally focus on one specific account, everything is easily lost in the maelstrom of social media utterance.
I am not panicking - not yet, I doubt that I will.
Why, well dear reader - Twitter is free, for free I get an excellent service and Twitter is able to occasionally ply promoted tweets into my timeline as well as for everyone else. The new proposition to adjust their model to promote some tweets is their call - it may work for me, I may find that it annoys me. Yet, I will watch and learn, observe and adjust my use of twitter.
After all - this isn't the only platform I use, it would not take any great effort to shift focus to Facebook, Google+ and LinkedIn which I also use.