The NYSE Arca continued its growth in 2007 with the addition of yet more exchange traded funds (ETFs). But new rumors could mean that it’s about to get even bigger as it gobbles up a rival.

Aaron Lucchetti of the Wall Street Journal reports that now, NYSE Euronext is rumored to be in talks to buy the Amex. The deal could be valued at $350 million if the exchange sells for a premium to its current implied price of about $320 million, say analysts. During a break at the Inside ETF conference, no one was around the Amex booth – a clear sign something was going on.

Last year, the NYSE Arca not only shifted to an all-electronic trading platform, but the exchange also added 121 new ETFs, 17 ETFs and 100 IPOs to its roster of 261 ETFs and ETNs. Listings-wise, the exchange was a bit behind its chief rival, the American Stock Exchange, which added 179 new funds — a 95% jump.

If the deal goes through, it could be a win-win situation: the Amex would find the buyer it’s been searching for, and the Amex would boost the NYSE’s listing, fund trading and stock-options businesses.

Tags: ETNs