Here is the website of the regulator in Malaysia, Jabatan Perlindungan Data Peribadi (Department of Personal Data Protection). I believe that it was launched last month. Some other websites refer to June 2012 as the expected time when the Act would come into operation.
However, it is not clear from the website whether the Act has actually come into effect. The website itself also seems to be a work in progress as some of the links did not seem to reflect the correct content or appeared to be placeholders (e.g. clicking on pemeriksaan, aduan & penyiasatan brings you to the home page instead of a page which related to investigations and complaints; the page on rights of data subjects (hak subjek data) brought you to a page which just displayed the word "kajian", which means study).
Either the Act is already in force (and everybody is expected to know about it), or it isn't. Whatever the case, it seems that Malaysia is coming
UPDATE: So, the answer to my initial question is "No". I made a call to the Department of Personal Data Protection, and was informed that the Act is not yet in force, and that it will probably come into force before the end of this year. Stay tuned.