Who is the 49ers biggest rival?

The last few months have seen the San Francisco 49ers and Seattle Seahawks engaging in an arms race of sorts, acquiring talent at a rapid pace. One team would make an addition and the other team would follow with their own big addition. It was personified with their acquisitions of Anquan Boldin and Percy Harvin.

Since Jim Harbaugh took over the 49ers and Pete Carroll took over the Seahawks, the on-field back and forth between these two teams has grown more intense. It has developed a rivalry that has been as good as any in the NFL. The Steelers and Ravens get some talk, and the Patriots and Colts used to before Peyton Manning left town, but I would argue that the 49ers and Seahawks bring the most intense current rivalry to the NFL.

That being said, will 49ers-Seahawks ever surpass 49ers-Cowboys? The 49ers and Cowboys squared off in 2011, 2008, 2005 and 2002 as part of the normal divisional rotation, but these two teams haven't played a meaningful game in 16 years. The last time they met with both teams holding a winning record was November 10, 1996, when the 49ers were 7-3 and the Cowboys were 6-4. Their last playoff matchup was the NFC Championship Game January 15, 1995, when the 49ers beat them 38-28.

Where do you rank the 49ers rivalry with the Seahawks compared to their other rivals? I view it as the bigger rivalry "right now", but can it ever surpass 49ers-Cowboys? Or maybe you even consider 49ers-Packers ahead of 49ers-Seahawks. Thoughts?