i talked to the same guy on live chat on both sites.
Chosen Answer:
Yes, they are. 
I wondered the same thing since I occasionally came across traces of blue host when working with my Hostmonster account. In fact, you can type “tracert yourhostmonsterdomain.com” at a Windows command prompt and see that Bluehost router just before hitting the hostmonster server. I suspected that HostMonster was either a reseller for Blue Host or rented server space at their facility.
Today I ran across a review that said they are both managed by the same company. Then I found another site that confirmed Blue Host bought HostMonster in 2005 and they are located at the same address.
See http://www.cheap-web-hosting-info.com/hosting_review.php?id=8
and
http://www.bluehostreview.org/bluehost-vsown-hostmonster/
by: thegeekette
on: 30th July 08
