If you remotely like RPG's and or adventure games then you're going to fall in love with Oblivion.
Even though it's early in the year, this is the best game so far bar none.
It truly is a great game and one of the best RPG's I have ever played.
Don't get me wrong, GRAW is a great game as well.
If you're a Recon fan then you'll be in heaven with this one and you might like it more than Oblivion.
Let me tell you how good Recon is, I wasn't a fan of the series but its made a fan out of me.
Both games are great, and honestly you cannot go wrong buying either one.
Actually, I would consider it a crime if you didn't buy both :-)
But perhaps you only have enough money to buy one of the two.
If I had a gun pointing to my head I would go with Oblivion.
Obviously that's unrealistic. So if you don't have the money, I suggest selling your body or something