It is true in Pennsylvania. Something like 17 delegates are assigned by the primary, and 50 or so are unbound.
I posted a thread w more info on the delegate process in PA
http://www.freerepublic.com/focus/f-news/3420183/posts
**********Pennsylvania voters will select three delegates from each of the 18 congressional districts. Those 54 delegates will be able to vote for whomever they want at the Republican National Convention.**
Its is complicated compared to other states primaries. The voters vote for 56 delegates who claim they are for candidate X. They do not vote directly for a candidate.