So, I'm finally getting protools, but I'm not sure if i should get regular 11 or HD. I know HD would be preferable in every way, but I'm not sure if I want to spend the money on that. I want to use it a lot for Sound for Picture stuff, so I looked to see what differences there were in it. Other then film editing, which i don't need, the only other difference was 1 track of video on regular versus 54 tracks on the HD. What does that mean?
First of all, I wouldn't say HD is preferable in every way. There are SOME functions that MAY force your hand. To answer your main question: Multiple video tracks allows you to have different video edits available in your session simultaneously.
The critical differences (in my opinion) are more important when working in Post or large music sessions. They are:
No/Low latency-important for multiple cue mixes on large sessions
new video engine-Allows you to open an AVID sequence's video without transcodding (ie converting which takes a LONG time for long form shows)
disk cache-audio is loaded into ram for quicker performance and eliminating the need for fast drives
surround mixing may be important for film work
advanced automation (punch capture, preview, etc.)-most POST workflows utilize these automation functions
VCA-some post and music workflows can take advantage of this function