If we look back to the beginning of 2011, Apple were worth in excess of $300 billion. Fast forward to the same time this year, and they posted record first-quarter results, with all-time record iPhone, iPad and Mac sales. Just 24 hours ago, Apple shares closed at $500, with a market capitalization of almost $470 billion.
So, from these pure facts, its not hard to see, if Apple continue on this meteoric growth, we could see them achieving a $1 trillion ($1,000,000,000,000) valuation. Apple is expected to launch their own TV later this year, the iPhone 5 is expected, the iPad 3 is expected, too. There are some devices that should sell tens of millions, all adding to Apple's non-stop growth.
Microsoft reached a market cap of $650 billion during the tech bubble back in 2000, so considering Apple sell way more devices than they did operating systems back then, it's not a stretch to think in the next 12-24 months, that we could see Apple hit the $1 trillion mark.