A wireless router is a combination of a wirless router and wireless access point. They are all croos platform compliant as long as it is an 802.11b. It is like advertising a hub or switch as cross platform clompliant. A wireless access point is just a hub. Most of the time a half duplex hub. (unless you spend a lot of extra money).
In our office we have 2 MAC desktops, a Mac laptop, 10 Win based PCs and 3 win based laptops. All access the wireless network flawlessly, AND I can even dump certian files on the MAC guys' machines without problems.