As originally drafted, “creditors” would have included anyone “who regularly extends, renews, or continues credit” or “who regularly arranges for the extension, renewal, or continuation of credit,” 15 U.S.C. § 1691a(e); see 15 U.S.C. § 1681a(r)(5). The new Act narrows this definition by excluding anyone who advances funds on behalf of a person for expenses incidental to a service provided by the creditor to that person. Examples of this exclusion would include a doctor who pays upfront for a test that a patient will reimburse him for later, or a lawyer who covers a filing fee for a client until his bill is paid.
For some reason, the FTC has not, until now, modified the old regulatory definition that was based on the original law. The new regulation catches up with the 2010 change in the law; this is all that changed in the regs:
(5) Creditor has the same meaning as in 15 U.S.C. 1681m(e)(4).
The FTC's own blog essentially acknowledges how simply this is, although it is less than clear in doing so.