The differences are very simple actually. VITC is recorded with the video and is located in the Vertical Interval, which is quite logical since VITC stands for Vertical Interval Time code.
LTC again self explanatory is Longitudinal TIme Code, which is recorded on a sopecial audio track.
The advantages of VITC is that it reads the time code better at low speeds and actually stopped on a freeze frame, LTC is guessing, albeit a damn good guess most of the time when stopped and can read quite well at low speeds.
Disadvantages of VITC it is overwritten when recording video. Thusly it can have a big jump in time code and can actually be different from the LTC time code in certain recording situations. as a result VITC is not good for the record end of editing. It can also be retained into the recording if not masked during the editing session.
My personal feelings are to refrain from using VITC in most situations because the disadvantages outweigh the advantages immensely.
I know this is not what you asked, but hope it help.
[Aaron]"Is frame accurate recapture from a LTC tape reliable?"
[Aaron]" Which one is largely broadcast spec."
Actually both, but broadcast spec isn't really an applicable definition of either.
[Aaron]"Does it depend on their station specs?"
Again not actually applicable.
LTC is much easier to work with for most all productions. If your equipment doesn't mask the VITC upon capture or editing, you could have both on the master and they will probably not be the same, which can confuse some equipment. You can never go wrong using LTC exclusively.
[Charlie King]"The advantages of VITC is that it reads the time code better at low speeds and actually stopped on a freeze frame, LTC is guessing, albeit a damn good guess most of the time when stopped and can read quite well at low speeds."
The "guessing" is usually done by counting control track pulses.
Also, While VITC excels at reading the tape at slow speeds, LTC is better at reading TC when shuttling the tape at fast speeds.