This excerpt taken from the PNC 10-K filed Mar 2, 2009.
Our acquisition of National City presents substantial risks and uncertainties, which could limit our ability to realize the anticipated benefits from this transaction.
On December 31, 2008, we acquired National City through a merger in which PNC continued as the surviving entity. We provide additional information about this acquisition in Note 2 Acquisitions and Divestitures included in the Notes To Consolidated Financial Statements in Item 8 of this Report.
This acquisition presents the following risks to PNC: