In the 2008 version of National Electrical Code, replacements were not required to be TR. However, now receptacles must be replaced with TR receptacles, if TR receptacles are required in that location.
As near as I can tell, nearly all dwelling unit receptacles must be TR as of 2014 code.
National Electrical Code 2014
Chapter 4 Equipment for General Use.
Article 406 Receptacles, Cord Connectors, and Attachment Plugs.
406.4 General Installation Requirements.
(D) Replacements. Replacement of receptacles shall comply with 406.4(D)(1) through (D)(6), as applicable. Arcfault circuit-interrupter and ground-fault circuit-interrupter type receptacles shall be installed in a readily accessible location.
(5) Tamper-Resistant Receptacles. Listed tamper-resistant receptacles shall be provided where replacements are made at receptacle outlets that are required to be tamper-resistant elsewhere in this Code.
406.12 Tamper Resistant Receptacles.
(A) Dwelling Units. In all areas specified in 210.52, all nonlocking-type 125-volt, 15-and 20-ampere receptacles shall be listed tamper-resistant receptacles.