Does a face and neck lift always include muscle tightening?

Almost all surgeons with proper training and experience will tighten up the muscle (more specifically, the SMAS), or do a deep plan (which includes the SMAS), so the short answer is yes.  There are exceptions to every case of course, in my experience. 

Thank you for the
question. To have an effective
and long-lasting lift, most surgeons believe in tightening the underlying 
musculoaponeurotic layer, which is known as SMAS. Skin is allowed to lie
naturally. In addition, it's common to also use your own fat to fill the
specific fat compartments of your face, in what is known as "lift and
fill" facelift by many authors. Combining the two is a very powerful tool
in facial rejuvenation. I would consult with a plastic surgeon and
discuss your specific goals. Please ask your surgeon
to show your before and after pictures of his/her patients to get a clear
understanding of what is involved in the procedure.
Pej Aflaki, M.D.
Johns Hopkins-trained plastic surgeon

This is a very good question.  There are many techniques available for facial rejuvenation.  The longest lasting results involve both muscle and skin tightening. In a skin only face lift, only the skin is elevated and re-positioned.  The standard face-lift today consists of elevation and tightening of the deeper structures of your face and neck muscles, combined with skin re-positioning. Avoid quick lifts and lunch time lifts, that are marketing ploys.  Please see a board certified plastic surgeon.