We intend to release a letter to all Dell shareholders shortly.— Carl Icahn (@Carl_C_Icahn) September 9, 2013
That's Icahn's 17th Tweet, and follows multiple takeover rejections by Dell's bid committee.
Regardless, it will be interesting to see market reaction when Dell shares begin trading at 2.30pm. Maybe more than the letter itself.
The more that Icahn uses Twitter to make announcements, the smaller his impact on the platform is likely to be.