Your Son as a recipient of gift will not owe any taxes. You also may not owe any gift tax but you will be required to file a gift tax return.
Normally a person can give up to the annual exclusion amount $12000 for 2007 to a person, every year ($ 24000 in 2007 if spouses joins in for the gift) without facing any gift taxes and note that such amounts do not count as part of your $1,000,000 lifetime total.
Further, IRS allows a person to give up to $1,000,000 in gifts, total, in their lifetime, before they start owing the gift tax. (This gift is not per (donee)person but its a per donor limit). So you can make gifts that are worth up to a million bucks during your lifetime without paying the gift tax. . Even if you do not owe a gift tax because you have not reached the $1,000,000 limit, you are still required to file gift tax return if you made a gift that does not qualify as excludable.
Let me know if you have any question. Bonus and Feedback will be highly appreciated!!!
Please note: This advice is provided with the understanding that all the relevant facts have been provided by you. Any change in facts might affect the advice given and hence may not be relied on in such cases.