seems to me that they went out and send a mass advertisement via PM for their "product".....
To me, it met the definition of spam because it was an unwanted advertisement that I did not ask for information for via PM.
According to SB TOS, it meets the definition of SPAM they have set out.
from
http://www.scubaboard.com/forums/faq.php?faq=tos_items#faq_tos_define_spam
On ScubaBoard we combine the commonly held definitions of SPAM into one concrete statement. SPAM is, as a general rule, a message sent in any amount of a commercial or non-commercial nature which is unsolicited. More specifically, SPAM generally consists of an advertisement of some nature which is sent directly to a user or users or is posted in a forum or forums.
SB could also ban them for this based on their TOS as the user is a new user who just came here to SPAM PM's. (they only had 2 posts at the time of the PM's).
The punishment for spamming a user or the board varies based on the severity of the SPAM. Users with no prior posts who blatantly post SPAM messages to multiple forums or PM multiple users may be banned without further warning. Users in good standing who send out a limited number of messages may simply be given a warning or a short suspension. There is no such thing as Good SPAM on our board and all members, regardless of their status, may be banned immediately for spamming the board in any manner even if it is with just one message or post. As a general rule we try to take into account the nature of all messages, commercial versus private and the degree of the abuse. But to this issue, simply do not send users messages containing advertising of services, goods, links or personal ads they aren't asking for!
EDIT: That being said, the pm's were diving related, so I don't really think we should kick them off the board, but perhaps some moderator should send them a PM explaining that there is a better way to fish up business.