Apple’s market capitalization is $469 billion. Let’s see what you can buy with $469 billion?
Microsoft’s market cap is $257 billion, and Intel is $136 billion. Throw in Dell for some chump change ($32 billion) and you still have $44 billion left to blow on beer and popcorn.
Alternatively if you wanted to go for a more “online model”, you could pick up Google for $199 billion, and throw in Ebay for $43 billion, Yahoo for $20 billion, LinkedIn ($8.5 billion), Amazon for $87 billion and still have $112 billion left to pick up things like Facebook (presently the IPO is not priced yet).
I’m not saying that Apple is a buy or a sell at existing prices, just that its market gigantic market capitalization means it will be facing the law of large numbers, mainly it becomes more and more difficult to increase your size on a constant percentage basis when you get bigger.