The loyalty to Nintendo is still as big as ever for me, and I still own only GC out of the 3 home consoles, but I won't even deny that lately I've been more then tempted to buy a PS2 as well. I enjoy playing my GC games, but the thing is there are games (in some genres) that are missing on the GC.
First of all we have no real Tennis games. Sega could have given us Virtua Tennis, but instead they gave us the lousy Virtua Soccer, which is by far one of the worse sports games ever. We also miss a good Rally game, and not to be forgetting the countless other 3rd party games we miss out on. There is no need to write about all the games that I would have liked to play on the GC, as that is a known issue.
But what bothers me the most, is all the great RPGs I as a GC only owner am missing out on. The good RPGs released on the GC can be counted on one hand, and as a RPG fan, it just is not enough for me. I want to play more RPGs as that is one of my favorite genres.
Basically what I'm saying is that, even people like me, who has been die hard Nintendo fans for almost 20 years, are now considering to buy atleast a second console, in addition to the Nintendo one, and if it continues like this, there is no other way for Nintendo then to turn into a 3rd party developer/publisher like Sega, and pull out of the hardware market.
I really don't see any future for Nintendo in the hardware market, if things stay as they are. Nintendo are getting killed out there. MS have taken over the 2nd spot, and Nintendo would be lucky to sell 10 million consoles in the next generation. I'm pretty sure MS will come out even harder the next time, now that they have established themselves. And most of GC owners own a second console anyway now. The PS2 owners do not.
About RE4, I doubt that it could have sold anymore GCs (atleast not increased the userbase drastically) by staying an exclusive, because a couple of games can not change the image Nintendo have managed to create for themselves. Nintendo have been too occupied with making profits, that they have forgotten that some losses now, could help them in the future. Nintendo should have paid/ivested more money to/in developers to develop new software for the GC.
At the moment, I regeret missing out on the PSX in the last generation and the PS2 in this one. 25 is too old for being blind on what the other consoles have to offer.