There are dozens of altcoins now but LTC is the only one with any real cap - and its purely a speculatve vehicle, whereas while BTC is mostly speculative, you _can_ actually exchange BTC directly for goods and or services in a rapidly increasing number of ways.

The ecosystem and brand awareness is novel for BTC, so in that respect I don't disagree with the analysis having focused solely on it - however, I do find their number (remarkably close to current price) a bit leading.