I'm not a tax expert but in researching expat matters I see a lot of references to rules, some fairly new, for U.S. citizens and residents on reporting FBAR, or Foreign Bank and Financial Accounts:
If you are a U.S. citizen or resident and have a foreign bank account or accounts with a total of US$10,000 or more in it/them, even briefly during the year and even if you earn no interest on the funds, or are an owner of a foreign corporation, or if you own offshore mutual funds (not based in the U.S.) the IRS says you are required to file a Foreign Bank and Financial Account Report (Form TD F 90-22.1), and penalties for failure to do so are steep.
Generally there are exceptions for non-income producing assets abroad such as land, but if you own the real estate through a foreign corporation you may have to file the report.
Willful failure to file can incur an annual penalty of US$100,000 or one-half the amount in the account, and even unwillful failure can incur a penalty of $10,000 for each infraction. You can be fined more than the value of the account. There also can be criminal penalties.
Tax experts say it's easy to unknowingly violate the rules, especially if you are married to a foreigner who has foreign bank accounts or have a child who is a student abroad and who has a joint foreign bank account with you, or if you have a power of attorney over a relative's foreign bank accounts, even if you've never exercised it.
Rules are complex, so you may want to see a tax advisor. Info from the IRS is at http://www.irs.gov/businesses/small/article/0,,id=148849,00.html (not sure why the link won't go active).
Forms must be filed on paper by June 30. Don't include it with your regular 1040. It has to be mailed separately to U.S. Dept. of the Treasury, P.O. Box 32621, Detroit, MI 48232-0621.