I just noticed this morning that when you have a multi-character word and you have "hide pinyin" turned on, the later syllables often appear for a half a second before disappearing behind the "show" buttons. Then when you finish writing a character or click on the first "show" button, they again appear for a second and then hide again.
This is on Windows XP, Chrome 5.0.342.9 beta, Flash player 10.0.45.2.
James