Text speak is frowned upon on the mailing list.
English is the language of the list, and you should use it to the best of your ability.
If you fail to observe this, expect to be chastised at the least.
There are some valid abbreviations used which can be found here - Some abbreviations used on the Feistfans-l Mailing List
Remember your on a mailing list for a published author. How would you like it if he started using text speak in his books ?
FAQ answers attributed to Raymond E. Feist are copyright by Raymond E. Feist.
It should also be born in mind that the answer given was only applicable on the date written, and to a specific question. You may find further, similar questions, in the FAQ.