Texas appellate e-filing continues to evolve at a rapid pace. Effective September 12, 2011, attorneys filing documents in the Texas Supreme Court must do so electronically. Pro se parties may e-file, or they may submit paper documents.
Don Cruse has broken down the new order over at the Supreme Court of Texas Blog.
Aside from SCOTX, e-filing is available in the following state appellate courts: Austin, Dallas, Eastland (new as of August 8), Houston (1st District), and Houston (14th District). The Texarkana court may be next in line, as its website states that e-filing will be available there soon.