newB: confusion about whois & DNS

[forrest gump]

Hello all,

Forgive me for being ignant... (and long winded)

I have recently been asked to administer a site that someone else has set up
and I'm really confused about some things:

background:
Cobalt Raq3 server
previously set up on an IP stack that is 208.155.xxx.xxx
domains are all set up a name-based virtual host
DNS server is local (I think) and run by the Raq3
hosting company recently changed its IPs to 66.84.xxx.xxx
All sites and dns entries in the Raq3 control panel were changed to new IPs
None of the domain's that the site hosts were updated through their domain
registrant (they all still point to ns2.lostmtn.com   208.155.79.150 and
ns3.lostmtn.com   208.155.79.151.  note that the IPs are the old IPs)

BUT, all the sites resolve properly!

I don't get it.  When I do a dig of any number of dns servers they all
respond

;; ANSWER SECTION:
www.lostmtn.com.        23h21m3s IN A   66.84.79.150

;; AUTHORITY SECTION:
lostmtn.com.            23h21m3s IN NS  www.lostmtn.com.

am I am surprised that they all have the right IP address.

Does this mean the whois server looks up the ns2.lostmtn.com and not the IP
address?

What am I looking at when I dig a certain ns server? (for example when I get
a response from ns1.bellatlantic.net, am I seeing their dns table? and if so
how are they getting the right IP address when the whois server lists the
wrong IP?  Does that mean they followed the ns2.lostmtn.com and updated
their tables from the Raq3s DNS entries?  Why is the sky blue?  Where do
babies come from?

I assume that the hosting company is going to stop paying for the old IP
stack in the near future.  Does that mean I am living on borrowed time?  At
that point will the domains stop resolving if I haven't updated their whois
entries by that time.

I'm practically afraid to change the whois entries for the domains at this
point since everything seems to be working (that and the fact that the
company who owns this server has no idea of what their client's domain
username and passwords are... I know that's going to be a royal pain!)


clearly you can see that my general knowledge of how the DNS system works is
not sufficient for understand what the hell is going on here... ANY and ALL
help will be GREATLY APPRECIATED!

thanks in advance for any help (and for even getting this far!)
Brian W.