Hi,
I am a non resident alien on OPT F1 visa until 30-SEP-2012 and on H1-B visa from 01-OCT-2012 onwards. I understand that I can claim standard deduction or there are certain itemized deductions that I can claim and out of these 2 I have specific questions about itemized deductions "travel expenses"

Can I deduct apartment rent, food, gas/car expenses, etc as part of travel expenses? Rationale behind this is my tax home is in india, and being on F1 on OPT which is limited to 1 year(which is a requirement to claim travel expenses), I am entitled to deduct these expenses from my income.

Can someone throw some light on this please?

You can claim standard deduction only if you are eligible to file resident tax return.
On nonresident return you get only itemized deductions.

I missed to mention that I was a student from India, so I can make use of the tax treaty to claim $5950 in standard deductions. But my question was regarding itemized deductions to maximize refund

The IRS does NOT consider your F-1 visa to be a temporary work assignment and would challenge your deduction of daily living expenses, so do NOT do it.

Thank you very much . I also have another question.

I moved to California on May 23 2011. I have not filed the California tax returns for both 2011 tax year and 2012 tax year yet(I am due to get refunds on both tax years).

I lived in California for 6.25 months in F1 OPT status during 2011.
What would be my residency status for tax year 2011 to file CA tax returns.

I lived in California for the entire 2012 tax year out of which 9 months were on F1 OPT visa and 3 months on H1-B visa. So what would be my tax residency status for tax year 2012 to file CA tax returns.