Been with Hostgator almost a year now and cannot fault them,
they are honoring the unlimited bandwidth & database space so far
and moved my db upto the big SQL server when it passed the 5Gig
mark. Since then the site has become more stable & faster.
As others have pointed out 15K page views a month is not that
big a resource drain for any good web host, unless they are either
really big pages or doing one helluva lot of processing server side.
Dare say one could find somebody running a large wordpress site
on free hosting with that kind of traffic.