I would consider those sites/pages to be advertisements that are subject to all of the regular requirements. Also, since it is unlikely that you can include a link to further information right next to your main message (I am assuming this), you would need to have any triggered disclosures right there.
IMHO, advertising on those types of sites is probably not a good idea. Those sites are generally seen as not very professional and especially for MySpace, hackers seem to get in to people's pages all the time.
Lastly, the examples you provided (0% repo loans, 4.51% checking accounts) are not compliant in their current form with advertising rules under Reg Z and Reg DD, respectively.
_________________________
I've just writed a wrong.