We've had our cable modem for a week.
Fantastic service & speed. 
No glitches whatsoever in connection. In all the speed tests I can find,
I average ~1Mbs.
I downloaded the largest file I could find: 74MB from Adobe's FTP site in
4.5 minutes. I have gotten Real Video streams where the server sets
the stream speed at 350Mb.
We downloaded the new version of the @Home software(Netscape ~22M)
& it takes longer for the PC to install the software than it does
to download it. The claim that the connection is 100 times faster than
dialup is true in our case.
I did find one way to degrade the performance: I have a cheap ISA ethernet
card & I changed it to full-duplex mode...wrong.
The install went flawlessly. The young lady tech had my PC connected
& up and running the service in less than an hour.
I did the setup on my wife's PC with no problems. 
We have a TV & VCR in the same room as the PC's and they use the same cable 
line as the modem with no problem. I have disconnected the modem a couple
of times to reroute wiring, etc. and it has no problem getting
a new signal lock.
Simply great technology! I plan to buy a modem in the near
future as the co. I work for manufactures them, which will bring the cost
to under $40/mo.
A recommendation: buy an ip address for each PC & use a hub to
connect the PC's to the modem...that way each machine is
independent & you don't have to fool with modem sharing.
The only problem we've had is that we've been waiting 6 months for our
area to get connected, but it's worth the wait!