That's how rumors get started.
First, you are mixing apples and oranges.
YES_ there was a change in the law this year regarding FERS Sick Leave, that goes half into effect in 2011, and the rest in 2014. NO, it has nothing to do with TSP. THAT change, the one regarding sick leave, is that FERS SICK LEAVE can be used to count time for retirement purposes. If you have a lot of sick leave on the books, you can use that to extend the number of years of service for the purpose of FERS calculation. One-half the sick leave time counts as of 2011, and it increases to allow all of it to count in 2014.
NEXT-
There IS a proposal to allow you to cash out ANNUAL leave and send it to the TSP- It's contained in H.R. 4865. That bill was introduced a few months ago, but is not of the House at this time. Since it's an election year, it's doubtful that one will be made law this year.
Here ya go:
http://thomas.loc.gov/cgi-bin/query/z?c111:H.R.4865:
It's a bill that has been proposed- it was requested by the President.
At the current time, it is sitting in the House of Representatives. No action expected at this time.
Here is the story from earlier this year, as carried on Federal News Radio:
http://www.federalnewsradio.com/?nid=19&sid=1912857