According to the guidelines, they're pretty strict:
Message Board Guidelines
Use of appropriate content is required. Abusive, profane and vulgar language, graphics and images will not be tolerated.
Personal attacks on or impersonation of players, management, employees of baseball and other users are not permitted. Personal attacks include, but are not limited to, the following: defamatory, sexual, and/or sexually implicit remarks.
Advertising, solicitations and chain letters are prohibited.
The cutting and pasting of copyrighted information is prohibited.
Posting information on accessing content that infringes or otherwise violates any intellectual property right, or any other proprietary right, of MLBAM or any third party is prohibited.
The posting of e-mail addresses and/or phone numbers of others is prohibited.
Posting of URLs and/or inappropriate images is prohibited.
Use the "Report Violations" option in the message "Option" pull down to report all violators.
I know, I know. Then again lots of "rules" in life are only as strong as the numbskull(s) enforcing them.
Occupy Message Board, maaaaaaaaaaaaaaaan.
Are not the MLB Guidelines copyrighted?
and pray, if so should they not