If you split with them and it comes down to a tie breaker the first tie breaker is W-L within division. That will probably be a tie now as well as the Seahawks are likely to blast the niners at the end of the year
There are only 7 playoff spots. That means the 4 division winners (Eagles, Bucs, Packers/Lions, Rams/Hawks) and three wild card teams (amongst these at the moment: 2nd place NFC Central, 2nd place NFC West, Bears/49ers/Vikings/Panthers). For me, the Rams beating the 9ers puts us in a better/more favorable position for a wild card spot.
As far as the division goes, just beat the Rams. If we split with them, from this vantage point a lot can happen with 8 games left in the season. Hell, Stafford could go down to injury, upsets, any number of things. Too early for such divisional tie-breaking scenarios for me.