I was once a fan of both, but not so much Soul Caliber anymore. The third game killed it for me. But Tekken has always wowed me, I feel a special connection to Tekken as I was playing it from day one, and have played every game on the day of release oddly. The same could be said for Soul Caliber I suppose, but I dont play that half as much as Tekken. At the moment Im whoring Tekken DR for the PSP, the game has upped the standards to what 3D fighting games on a handheld should be. And playing Tekken is almost standard whenever I get the chance to go to an arcade.
I will buy Tekken 6, probably not on release as I probably wont have a PS3 by then, but eventually. Soul Caliber 4 can pass, unless the series can drastically move from its roots in the next installment.
I hate it when people use this against Tekken. The same is with most fighters, especially Soul Caliber.