I signed up with FilipinaHeart & after doing so i emailed them asking about that exact subject
they responded with the following message
...
 Dear member,
Thank you for contacting us.
Please be advised that section 4 (B) (ii) of IMBRA exempts dating 
companies whose principal business is not to provide dating services 
between US citizens and foreign nationals so long as it charges comparable 
rates and offers comparable services to all individuals regardless of 
gender or country of citizenship. Consequently our company is exempt as it 
falls within this exemption (as do many other large dating companies). 
Full information regarding IMBRA can be found at 
http://usaimmigrationattorney.com/images/IMBRA2005.pdf...
I hope this info helps
piglett