P.,
You posted largely the same thing very recently. Give him some more time -- two weeks in preschool is not much and he is going to need time to adjust; however, you also do need to have him evaluated by a developmental specialist. Don't rely just on your pediatrician; ask for a referral. Your son does need to be tested to see why his development is taking this particular direction. While it's great that he makes eye contact, looks for your approval, is keyed into things outside himself like songs and movies and stories -- he does need evaluation.
I remember the earlier post and I think you seemed reluctant in that post to go to a professional -- almost as if you were resistant to the idea that he might have some form of diagnosable condition. You say again here that you are sure he does not have autism; that word seems to scare you and you insist he doesn't have it, but he may be "on the spectrum"; you can't diagnose one way or the other, or he may have other non-autism developmental issues -- unless you are a trained, experienced professional you can't tell. Please be open to the idea that despite his wonderful attributes of singing, reciting stories, etc., he does lack normal communication skills that he should have at this point. Please be open to going to a professional. Now.
Having him in preschool is great, but you cannot rely on that to get him to talk. It can help him get there, but he really does need professional medical evaluation alongside preschool -- preschool cannot replace a medical evaluation.
Also, frankly, very soon (if they haven't already) the preschool is going to come to you and say that he must be evaluated, possibly even in order to stay there. They will soon be asking you why he does not communicate other than in poems and why he cannot follow any directions at all. They are going to come to you about this if they haven't already. What do you plan to tell them? They are likely to insist that he be evaluated and possibly diagnosed in order to remain in the preschool.
I notice too that you mention you're trying to stop letting him point etc. in order to tell you what he wants -- you're stopping the pampering you mentioned in the first post. That's great, but it's also going to take time and tremendous consistency; keep it up, but be sure that everyone in the family, not just you and your husband, refuses to let your son point to get what he wants.
Good luck and keep up the steps like preschool and insisting he use words.