Completed my first acrylic painting on wood this afternoon. Wood definitely has a different feel than canvas. It absorbs water and paint quickly, so there is less forgiveness, but it makes up for it with its smooth surface. I'll be trying it again.
Acrylic is a resilient medium. You could take a finished canvas, tie it around your neck like a cape, dive under water, and sans sharks and unruly penguins, return with it largely unscathed. Despite this fact, it's a good idea to seal the canvas with coats of varnish. I just picked some up last week and am now in the process of going through all my acrylic canvases and covering them with varnish (which resembles diluted glue). I'm using a medium matte type, so it doesn't appear to change the colors or look of my finished paintings. However, I encountered a problem when using the varnish on my painting that is a combination of acrylic and ink. The varnish makes the ink disolve and run. Not good. Fortunately, I was able to minimize the damage, but am now confused on how to protect my other combination acrylic and ink paintings.