In-room wireless requires a larger coverage area, but the same back-end public access portal and payment infrastructure. If you don't already have that infrastructure and want to work with a company specializing in hotel or hospitality Wi-Fi, check out offerings from iBAHN, Wayport, StayOnline, or Hotel Wireless. If you'd rather roll your own, look at controllers that incorporate guest Internet access portals, available from vendors like HP (Colubris), Meraki, Ruckus Wireless, and Bluesocket (to name just a few).
As for blanketing rooms with coverage, the traditional approach was to conduct a site survey and install APs on each floor, connected to a controller using wired Ethernet. You might do this if your hotel is already wired for Ethernet, but a less expensive and far more flexible solution is to install APs interconnected by wireless mesh backhaul. There are clear advantages to a dynamic wireless mesh in a venue like a hotel, not the least of which is that you can quickly and easily modify coverage to reflect usage, budget, and back-fill problem areas.
A few resources that you might want to check out: http://www.ruckuswireless.com/enterprises/hospitality http://www.bluesocket.com/industries/public http://www.antamediahotspot.com/hotel-wifi/
This was first published in September 2010