The fun will really start once the IRS begins auditing 2010 corporate returns with Schedule UTPs.

FORBES: Will The 2010 Schedule UTP Provide The IRS 20/20 Hindsight For Prior Tax Years Currently Under Audit?

However, the great unknown is whether, and to what extent, the IRS might analyze Schedule UTPs filed for 2010 as an aid in identifying uncertain tax positions for earlier years under audit.

FORBES: Will The 2010 Schedule UTP Provide The IRS 20/20 Hindsight For Prior Tax Years Currently Under Audit?

By September 2011 (when most corporations with calendar tax years will have filed their returns under extension), IRS Agents will be in some stage of auditing large corporate taxpayers for years prior to 2010 when the first round of Schedule UTPs are filed.

FORBES: Will The 2010 Schedule UTP Provide The IRS 20/20 Hindsight For Prior Tax Years Currently Under Audit?