The IRS today issued final regulations (T.D. 9209) under § 179:

These final regulations provide guidance to taxpayers for making and revoking elections to expense the cost of property under § 179. The regulations reflect changes to § 179 made by the Jobs and Growth Relief Reconciliation Act of 2003 and the American Jobs Creation Act of 2004. The changes made to § 179 permit small business taxpayers to make or revoke § 179 elections on amended returns without the Commissioner’s consent. This provides flexibility to small business taxpayers in determining whether the § 179 election is to their advantage or disadvantage.