In a move that will spur talk about a much-anticipated initial public offering, social game publisher Zynga hired a new chief financial officer today.

Dave Wehner, former managing director at Allen & Co., will be the new CFO. Wehner has worked at Allen & Co., the media and technology investment bank headed by Herb Allen, since 2001. He replaces Mark Vranesh, who becomes Zynga’s chief accounting officer, reporting to Wehner. A source familiar with matter says that the hiring does not signal that an IPO is coming soon. Given his background, it might be more likely that Zynga will continue its string of acquisitions.

Zynga declines to comment on whether it will do an IPO. With its private valuation estimated at around $4 billion to $5 billion, the IPO could be one of the biggest events in the young social gaming market, where Zynga dominates the field. While it has the best hope of doing an IPO, Zynga has also raised $520 million, a considerable war chest that can actually help it postpone an IPO. (Facebook itself is rumored to be delaying its IPO until 2012.)

About $150 million of that amount was raised by Zynga this week from SoftBank, which has formed a Japanese joint venture with Zynga to publish social games in Japan’s mobile and PC markets. Another $150 million is expected to come from Google.

Wehner led corporate finance teams at Allen & Co. Those teams raised capital and assisted with acquisitions for the firm’s Silicon Valley clients. Wehner also was involved in Allen’s principal investing activity, sponsoring the firm’s investments in Pandora, Quantcast and StubHub. Before joining Allen & Co., he worked as vice president of corporate development for an e-commerce startup and at the tech investment banking firm Hambrecht & Quist.