Yep Ken, this is another case of innocuous inline styles being stripped by the wiki editor upon save. Been there, done that, have already complained about it in beta.
Meanwhile, I've found that I've had more success using deprecated constructs such as img align="center". I believe this still works in all browsers but that could [of course] change someday.
Hope this helps,
Bruce
--
The system Help is your friend.??
/static/help