Bang for the buck: Wireless router or access point

I'm looking to add a wireless access point to my existing wired only network at home. I'm only thinking about wireless because I'm thinking of getting a squeezebox, and I'd like it to be wireless.

I figure that I only an access point, I'm very happy with my existing router and switches. But it seems like the access points are slightly more than comparable wireless routers. For instance I see the linksys WAP54g as being $7(canadian) more than the WRT54g.

Are there any advantages to getting an access point over a router? (I'm thinking perhaps less delay due to encryption) Or are the routers just cheaper because there is a larger supply and I'm better off getting a router and using it as an access point.

Thanks!