Can we say the first sentence is subjective because it is asking about subject? And can we say the second sentence is objective because it is asking about object?
The question is subjective / objective or the word who?
1) Who is talking to Tommy?
2) Who is Tommy talking to?
NOT A TEACHER
(1) What an interesting question. I learned something new today.
(2) I did some googling, and I discovered that you may be close to correct.
(3) I found a Google book entitled Reformed English Grammar written by a Mr. John Coghlan in the year of 1868!
(a) He says that a "subjective sentence" is one that contains the subjective [case] without an objective case: The king reigns [rules].
(b) He says that an "objective sentence" includes an objective case: The king rules his subjects. [My note: "subjects" is in the objective case. The same as: The king rules them.]
(4) IF we accept Mr. Coghlan's idea, then it would appear that both of your sentences are so-called "objective sentences," for they both contain the objective case:
(a) Who is talking to Tommy? ("Tommy" is in the objective case. Compare: Who is talking to him?)
(b) Who(m) is Tommy talking to? = Tommy is talking to who(m)? (As you know, "whom" is the objective case of "who"; as you also know, the objective case is necessary after a preposition such as "to.")
(5) I most respectfully suggest that you be very careful about using those terms.
Perhaps in the year of 2011, teachers in English-speaking countries do not use those
terms in modern textbooks.
(a) Usually people use those terms this way:
(i) Subjective sentence (an opinion): The Parser is stupid.
(ii) Objective sentence (a fact): The Parser is a member of usingenglish. com.
To an average speaker of English, if you say "That's a subjective statement" it means that you have said something that is influenced by your opinions, and if you say "That's an objective statement" it means you have said something that is based on facts and empirical observation only.
The typical speaker of English would not be thinking about grammatical subject or grammatical object.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
For those interested in such matters, note TheParser's use of the subjunctive 'be'. This is correct, though it would be quite unusual in BrE. Most people on our side of the pond would be more likely to say "I suggest that you are/should be very careful". I tend to use the subjunctive myself, but I am both old and old-fashioned.
I'm impressed by TP's discovery - that 1868 'grammar' book - and it's worth pointing out, in addition to Barb's comment about 'subjective', that there's a simiilar more-common [that is, more common than the archaic meaning, not more common than 'subjective'] meaning for 'objective'.
A 'That statement is subjective.' (That is, its meaning is highly coloured by the beliefs of the speaker.)
B 'On the contrary, it's perfectly objective. The figures speak for themselves.'