What is the literal translation of Isaiah 53:8? In KJV it says:
... for the transgression of my people was he stricken
, but according to this http://www.youtube.com/watch?v=PwwRGCOKuMA#t=4440 it says "To them", not "To Him".
As a strict language question, that should be asked on Hebrew.SE, which is where I think the question is coming from. From a Jewish perspective, it refers to the "my people" in that sentence.
From a strict language point of view, it could arguably be ambiguous (מו - the suffix is sometimes singular if the context indicates it), however according to all of the uses of the full word למו that I have seen here it is plural.
Also, notably the standard term for them is להם which is pronounced La-Hem, but in order to make it more in tune with עמי - my people, pronounced A-Mi, it uses למו - La-Mo. If it wanted to say "him" it could have used לו - Lo, which would have the same vowel association without the ambiguity. (The Radak on the verse in question says that it should have used לו if it wanted to say him, directly addressing the Christian claim).
So regardless of the language argument of could it be singular (as I said, see Hebrew.SE) it very clearly could be plural, and seems to reference "my people". Which is why I don't understand the energy on this issue. At most you could demonstrate a plausible alternative reading, but hardly a compelling one.