I personally think that peoples angst, about vlan filtering affect on CPU as something evils is too broad brush an approach.
For most home owners the ease and convenience of vlan setups as per
http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1
Is a great way to go.
I am sure for enterprise scenarios the throughput (CPU load) is critical but thats not everybody.
Caveat that is just an opinion from a non IT trained layperson with no MT credentials.
I prefer keep it simple!