I think the main reasons why acrylic tanks are as popular as they are, are that they're lighter, harder to crack, and they can be made into virtually any shape you can think of.
That being said, glass is cheaper, easier to maintain, and can support more than its own weight over distances. With acrylic tanks, you have to have a stand that supports the ENTIRE bottom unless it has a very thick bottom.
Light refraction is also something to consider. Glass tanks have to bend light all sorts of ways. So looking at a fish through a glass tank can be slightly skewed. Whereas with an acrylic tank, its refraction index is closer to water so things like color, size, and position are closer to what it actually is.
Glass stays clearer longer than acrylic which has a tendency to yellow with age.
Lastly glass tanks are easier to make and therefore are cheaper.
When all is said in done, unless the tank is unusually large or you want it in a different shape than rectangular, I'd still go with glass.
