AtlantaTaxExpert:

Thank you for your response. It definitely helps me. The only question is why I have to wait until June 1, 2010? Is the requirement is to be in US for at least 9 months? Do you mean if I choose to do so I don't have to file tax return this year. There is no penalty for this? Because tax season ends in April, 2010.

Thank you.

First, you can file an extension (which is automatically approved) to file by 15 October 2010.

Second, you must wait until 1 June 2010 to meet the Substantial Presence Test. This is the criteria specified in IRS Pub 519, which can be downloaded and studied at your leisure at Internal Revenue Service.