For a recipient of the inheritance - does not need to claim it as income. Please see for reference IRS publication 525 page 30 - http://www.irs.gov/pub/irs-pdf/p525.pdf
Only if the inherited money were in tax deferred account - such as IRA, 401k, etc - and you are taking distribution from that account - the distributed amount will be your taxable income.
Oregon inheritance tax is levied on the value of the assets of the decedent. For 2007 an estate with a gross value of $1,000,000 or more should file an estate tax return. The unified credit amount is $345,800. - http://egov.oregon.gov/DOR/BUS/inher-general.shtml see also - http://egov.oregon.gov/DOR/BUS/inher-adv.shtml