http://biz.yahoo.com/ap/070327/fcc_internet_device.html?.v=1

If this occurs, the line between them will be awfully thin.

Does anyone know how much bandwidth airwaves can provide? I'm curious if this would be useful for anything other than sending emails, or light web surfing.

The analog bandwidth requirement depends on the symbol rate.

"Symbol rate =bit rate/the number of bits transmitted with each symbol

Symbol rate is sometimes called baud
rate. Note that baud rate is not the same as bit
rate. These terms are often confused. If more bits
can be sent with each symbol, then the same
amount of data can be sent in a narrower spectrum.
This is why modulation formats that are
more complex and use a higher number of states
can send the same information over a narrower
piece of the RF spectrum."

Of course, there are many different ways to digitally modulate:

"Modulation format ::Application
MSK, GMSK ::GSM, CDPD
BPSK ::Deep space telemetry, cable modems
QPSK, ?/4 DQPSK ::Satellite, CDMA, NADC, TETRA, PHS, PDC,
LMDS, DVB-S, cable (return path), cable modems, TFTS
OQPSK ::CDMA, satellite
FSK, GFSK:: DECT, paging, RAM mobile data, AMPS, CT2, ERMES, land mobile, public safety
8, 16 VSB ::North American digital TV (ATV), broadcast, cable
8PSK ::Satellite, aircraft, telemetry pilots for monitoring broadband video systems
16 QAM ::Microwave digital radio, modems, DVB-C, DVB-T
32 QAM ::Terrestrial microwave, DVB-T
64 QAM ::DVB-C, modems, broadband set top boxes, MMDS
256 QAM ::Modems, DVB-C (Europe), Digital Video (US)"

http://cp.literature.agilent.com/litweb/pdf/5965-7160E.pdf

There are so many different types of digital modulation techniques, there is no simple answer to your question.
Also, it does matter whether you are broadcasting from one transmitter to many receivers or one receiver as in fiber optics.

http://www.fiber-optics.info/articles/analog-v-digital.htm

In addition, there are scientific limits, and FCC limits.

http://www.tvtechnology.com/pages/s.0001/t.1203.html

Got that?

I know who I am going to for all my tech questions now! I only vaguely recognized the shapes in your post as being from the english alphabet, other than that I was lost...

Thanks for the info!

Eureka-147 (DAB) uses OFDM.
Orthogonal Frequency-Division Multiplexing (OFDM)

OFDM has developed into a popular scheme for wideband digital communication systems. Examples of applications are:

ADSL, SDSL and VDSL broadband access via POTS copper wiring.
Certain Wi-Fi (IEEE 802.11a/g) Wireless LANs.
DAB systems EUREKA 147, Digital Radio Mondiale, HD Radio, T-DMB and ISDB-TSB.
DVB terrestrial digital TV systems DVB-T, DVB-H, T-DMB and ISDB-T.
IEEE 802.16 or WiMAX Wireless MANs.
IEEE 802.20 or Mobile Broadband Wireless Access (MBWA) systems.
Flash-OFDM cellular systems.
Certain Ultra wideband (UWB) systems.
Power line communication (PLC).
MoCA home networking.

Don't forget GOSC, or good old stringed cans -- virtually unhackable.