Hi,

In 2008 my (then) fiance's K1 visa got approved and we got married in September in the USA. He's from Mexico and we went through the normal K1 process (he's from Mexico, we met in Mexico, his first time in the US was after the K1 approval).

Here's a little more info:
January-August he worked in Mexico (converted to USD, would be less than $2000 for the year, and I worked in the USA for all of 2008)
August 26, he arrived in the USA
September we married in the USA
October we filed Adjustment of Status and Employment Authorization from DHS

January 2009 - he received his Employment Authorization from DHS and started working

At this point, he hasn't received his permanent residency yet, so he's a nonresident alien.

So my questions are... for tax purposes, what form would we/he need to fill out for outside US income? He has his SSN already, and we're filing jointly. What other important info do I need to tell IRS? Other than a mortgage and an IRA that I haven't touched since 2006, the only change from last year's tax return is my marriage, so can I still just use the 1040 and write a statement saying that we would like him to be considered a US resident for all of 2008?

Thanks,
Nm

If you are a U.S. citizen or resident, then you can file joint return as residents. You can do this even if your spouse has never been to the U.S. and is non-resident.
You must both report your worldwide income. Read: Your U.S. Tax Return: U.S. Citizen or Resident with Foreign Income

I'm looking at the Form 2555-EZ and am even more confused... I think he doesn't meet the Bona Fide Residence Test, so I looked at the Physical Presence test. At first I didn't think my husband would meet the Physical Presence test because he wasn't in Mexico for more than 330 days in 2008, but then it says "or any other period of 12 months in a row starting or ending in 2008" - and in that case, would he meet the Physical Presence test since he left Mexico in 2008??

And then, what is a Tax Home? The country from which one pays taxes?

This 330 days period can start in 2007 and end in 2008 or start in 2008 and end in 2009.
Read IRS publication 59.

Your husband was NOT a resident alien for the entire period involved in the Form 2555, so he CANNOT file to claim Foreign Income Exclusion.

He CAN claim the Foreign Tax Credit (Form 1116) if income taxes were assessed and collected on his Mexico-based earned income.

Even if not Foreign Tax Credit applies, the benefits of filing jointly MORE than compensate for reporting the added Mexicol-sourced on your tax return.

File jointly and claim the Mexican income.