I'm Comcastic!
Ugh. I finally bit the bullet, and had Comcast "Workplace" service installed to replace the flakey fixed-point wireless service I've been fighting with for the past two years. To be fair, I should qualify that: my "last mile" link (between my rooftop transmitter and the tower) has been rock solid. The problem has always been mid-day routing and configuration changes on the part of the provider, which have knocked me offline anywhere from a few minutes now and then, to one incident that had me offline for the better part of a day. At this price and service level, that's completely unacceptable. So, since I can't get service from my preferred vendor here due to a complete lack of DSL availability in my area, I'm stuck with the local cable company: Comcast.
So, first impressions (note that I haven't moved ANY services to this yet,
until I get a feel for how this will work): 6Mbps download speeds are
unbelievably fun. 
The 768kbps upload speed may end up being a bit of a
hindrance; most of my traffic is
SMTP, but I do receive
a fair bit of HTTP
traffic too, and that's where that upload bottleneck is going to suck
(specifically, both I and Erica
maintain pretty large photo galleries that seem to get a bit of traffic,
and I'll often host larger items for people for limited times). But, we'll
have no idea how that'll go until I bite the bullet and cut stuff over; I'm
hoping I can run fairly well off of both links for a while, with plenty of
time for DNS updates to propagate.
Ugh. I remember how much I hate renumbering now.