Seems we share another of the finer tastes in life, what with the mighty Chels, which is cool because I wrongly assumed you were a lagerer!
Definitely do the IJ, it's cool. Think they do a free tour on Fridays? Make sure you taste from left to right on the pumps or it might be a quick visit! You can also have a sly chuff if you take your beer over to the canalside; we had been a few times before and never felt we should but the last time all the young locals who were there did it like it was a usual thing so we joined them.
http://deprael.nl/
Gapie from the forum works here (you must have met him?) and is always happy and generous to show people round. This is the only other real microbrewery in Amsterdam if you can believe it!
http://www.arendsnest.nl/english.php
Though not a micro this is a bar that only sells Dutch beer, huge selection, were once a little sniffy with us when we turned up red-eyed and reeking of the ganj, but mellowed when it became clear we knew our beery stuff too.
http://www.beertemple.nl/index.php
This is another bar run by the same guy that specialises in craft beer from the USA, mega hoppy IPA's and lots of other crazy flavours if you like that style.
Would have loved to show you round but think we miss each other in town by about a week.