Looks like I can't reach several of Comcast's fiber/coax customers in Oregon and Washington:
grps-edge-rtr-1#trace 75.145.64.XXX
Type escape sequence to abort.
Tracing the route to 75-145-64-XXX-Oregon.hfc.comcastbusiness.net (75.145.64.XXX)
1 fa-6-0.grps-edge-rtr-2.visp.net (208.74.128.9) 0 msec 4 msec 0 msec
2 c1-mdfd-s40-visp.mind.net (69.9.134.65) [AS 6296] 0 msec 4 msec 0 msec
3 so-2-1-0.ar2.SEA1.gblx.net (64.212.109.181) [AS 3549] 12 msec 12 msec 12 msec
4 pos10-0-2488M.cr1.SEA1.gblx.net (67.17.71.182) [AS 3549] !H * !H
Our NOC has had several calls from folks using Comcast who weren't able to reach us, and we then confirmed that they had no network connectivity whatsoever...
As a Comcast customer in the NW, I see the same thing outbound.
Traceroute to some sites die in glbx, and other sites work via other
transit providers.
Here is the reverse view from one of my systems on residential Comcast
in the Everett/Mill Creek area (source is 76.121.150.xxx):
Tracing route to 208.74.128.9 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms 192.168.254.254
2 * * * Request timed out.
3 9 ms * 9 ms
ge-1-8-ur01.everett.wa.seattle.comcast.net [68.86.177.117]
4 10 ms * 18 ms
te-9-1-ar01.burien.wa.seattle.comcast.net [68.86.96.177]
5 10 ms * 11 ms
te-9-1-ar02.burien.wa.seattle.comcast.net [68.86.96.170]
6 11 ms 9 ms 9 ms
te-8-1-ar02.seattle.wa.seattle.comcast.net [68.86.96.134]
7 11 ms 11 ms 12 ms
te-9-1-ar02.seattle.wa.seattle.comcast.net [68.86.90.210]
8 11 ms 11 ms 12 ms
COMCAST-IP-SERVICES.TenGigabitethernet1-4.ar5.SEA1.gblx.net
[64.209.111.94]
9 10 ms 11 ms 11 ms TenGigabitethernet1-4.ar5.SEA1.gblx.net
[64.209.111.93]
10 38 ms 38 ms 39 ms
Prime-Time-Ventures.so-2-1-0.ar2.SEA1.gblx.net [64.212.109.182]
11 39 ms 40 ms 38 ms 208.74.128.9
Michael Acosta wrote:
As a Comcast customer in the NW, I see the same thing outbound.
Traceroute to some sites die in glbx, and other sites work via other
transit providers.
Looks like whatever the SNAFU between Comcast and GLBX was, it's been resolved for some time now... 
Cheers,
I have a Comcast business line, and have bbeen up all day. Here is
my trace to the same IP (from Bremerton WA):
orion@orion:~/tmp$ traceroute 208.74.128.9
traceroute to 208.74.128.9 (208.74.128.9), 30 hops max, 38 byte packets
1 73.96.188.1 (73.96.188.1) 8.051 ms 11.888 ms 6.731 ms
2 GE-2-35-ur01.bremerton.wa.seattle.comcast.net (68.86.98.81) 8.541 ms 7.219 ms *
3 te-7-3-ar01.burien.wa.seattle.comcast.net (68.86.96.46) 13.948 ms 8.413 ms *
4 * * te-9-1-ar02.burien.wa.seattle.comcast.net (68.86.96.170) 9.484 ms
5 te-7-4-ar02.seattle.wa.seattle.comcast.net (68.86.96.198) 9.429 ms 10.701 ms 10.251 ms
6 te-9-1-ar02.seattle.wa.seattle.comcast.net (68.86.90.210) 13.720 ms 11.470 ms 10.241 ms
7 * * *
8 TenGigabitethernet1-4.ar5.SEA1.gblx.net (64.209.111.93) 13.467 ms 12.165 ms 10.647 ms
9 Prime-Time-Ventures.so-2-1-0.ar2.SEA1.gblx.net (64.212.109.182) 36.033 ms 40.281 ms 36.884 ms
10 gp-edge-04.visp.net (69.9.134.66) 44.607 ms * 39.161 ms