Well sure, what else is new in cricket? Twenty/20 is inserted in almost every series now. IPL’s second season alongwith ECB’s Stanford deal next year are on the horizon already. If introducing this version of cricket in the expatriate market - US/China - will help realize and promote further test cricket in these markets (which I frankly don’t see happening as a result of it), by all means, let Twenty/20 be a part of the Olympics in a bid that it will improve test cricket.
“I believe that in time the success of cricket at the Olympic Games will lead to more Test-playing nations, something that the sport will need in the coming century.” (Gilchrist on CricInfo)
How does this statement even relate to the promotion of test cricket? More countries does not mean better competition. If the likes of USA and China start playing test cricket, that would still leave a big gap for them to reach up to the levels of regular test-playing countries.