Creating a Logic Gates
First off - don't believe everything you read - the single transistor may be crude but it works. Where it falls down is that its not particularly fast switching or useful when you come to design integrated circuits. The 'replacement circuit' is the basis of a ttl logic gate. (7400 series) which has subsequently been replaced by CMOS circuitry which at some point in the future will be replaced by something else.

If all you want is a simple (single) NOT gate then the single transistor could be way to go. It all depends on the requirements of your circuit (speed, voltage range, logic levels etc.)  

The main problems are; 

(1) fanout - how much current can you take from the output without lowering the output voltage too much.

(2) Logic level tolerence (noise margin) - What value of voltage constitutes a '1' or a '0'. In a one transistor circuit anything over 0.6V would be seen as a '1'. The saturation of the transistor may be 0.3V so it doesn't leave much of margin for error.