Leaving aside the eggs-in-a-single-basket aspect, I think being too close could be a liability. You may read a lot of bearish press about Apple that emphasizes market share over profit share completely missing the point of Apple's culture and the fact that foregoing the standard protectionism is what allows them to pursue the next great product so much better than anyone else. You might be totally right in this thinking and yet still be screwed by the market because it's full of speculators subscribing the conventional wisdom. And it's tech, so totally plausible for them to hold the stock down until consumer tastes move on and it becomes a self-fulfilling prophecy.

I see so much dubious analysis of Apple (eg. suggesting Apple could go the Dell route) that I'm getting tempted to go long, but it's a tremendous risk because it's so damn frothy.