LAST EDITED ON Apr-17-08 AT 06:18 PM (PST)
 
(Edited to reflect that AND is not OR )

It's not that easy to find all the rules that apply to Hubpages. Their user agreement isn't linked from anywhere obvious (it's at http://hubpages.com/help/user_agreement) and although they say that it's the "Entire Agreement" it patently isn't because they use certain terms in there that are only defined elsewhere (and after a lot of digging). There are still more rules (like the "no follow" one) that I only found buried deep in a forum response.

The rules on commercial hubs:

Commercial hubs are required to have an ad level setting of High. Your hub is considered to be commercial if it meets any of these conditions.

* it is monetized through a non-hubpages affiliate mechanism
* it contains links to other commercial sites
* it promotes a for profit business, especially a business that you have an interest in

The "overly-promotional" flag:

1) Revenue should only come from "revenue capsules", i.e. the Amazon, eBay and Adsense profit-sharing capsules. You do have to use your own affiliate IDs to take part in these. You also get a % of the profit share from Hubbers that you refer (this share comes from Hubpages, not from the Hubber)

2) "Outbound links to other sites where you can make revenue are banned ... UNLESS you give HubPages something valuable (original and exclusive content) in exchange for links from HubPages to your money sites. And the rate of exchange is one (1) Hub of unique and exclusive content for each two (2) commercial links. "

3) All links must be relevant to the topic of hub.

No follow

Links are no follow on hubs with a Hub Score of 50 or less or where the Hubber has a score of 75 or less. Unless the high scores are maintained, links will become no follow again automatically.

Links in Hub comments are all no follow.

It makes sense to put a photo in your profile and not to publish more than 2 hubs a day, maximum.

Isobel