NetworkWorld published an article citing research from
Probe Research ranking the top 10 ISPs and their marketshare
based on Year-end (2000) revenue.
1. Worldcom (27.9%)
2. AT&T (10%)
3. Sprint (6.5%)
4. Genuity (6.3%)
5. PSINet (4.1%)
6. Cable & Wireless (3.5%)
7. XO Communications (2.8%)
8. Verio (2.6%)
9. Qwest (1.5%)
10. Global Crossing (1.3%)
Since PSI is larger than C&W, that C&W should pay for transit 
I don't know what happened to Level 3, ELI, @HOME, Broadwing,
or all the non-US ISPs.
http://www.nwfusion.com/newsletters/isp/2001/00846039.html
Essentially none of these sorts of analyses
are meaningful or relevant because one can yield
any result or ordering one wants by playing games
with the definition of "ISP" and the basis for
the ranking.
Also very unclear to me how any of this
helps folks operate their networks or is applicable
to NANOG, unless we've become a marketing organisation
recently...
Ran
>NetworkWorld published an article citing research from
>Probe Research ranking the top 10 ISPs and their marketshare
>based on Year-end (2000) revenue.
Essentially none of these sorts of analyses
are meaningful or relevant because one can yield
any result or ordering one wants by playing games
with the definition of "ISP" and the basis for
the ranking.
Well - I think Genuity is the #1 ISP - since they use AS 1
(They got AS1 when they bought(merged in ?) BBN ) and it's quite obvious
that the ISP with the #1 Autonomous System is the best - right ? ( 
Rafi
Everybody knows that Real Programmers start counting from zero.
The local Genuity folks gave me a very nice mouse pad, with
a huge "AS1" in about 80-pt letters very visible from a
distance.
Now I have people stopping by to ask who "ASS ONE" is. I
tell them it's Genuity, they're proud to be it, and in fact
they paid a whole bunch of money to become it, so they want
everyone to know. They advertise it to every Internet router
they can, especially their competitors'.
Just waiting for the ad campaign: "We Kick Genuity's AS"
Pete.