I can't remember so I'll ask again

What is the new Polling delay for wind direction/temperature do?

default is 30
but you can make it longer if you PC is an older pc
so that wd is not so cpu intensive
you can make it faster if cpu use is not a worry
(as the dallas 1 wire temperature read, etc, is cpu intensive)

So does it mean that the temperature and wind direction is only read every 30 seconds if this value is set to 30? If so this is cool and may smooth the graphs out.

yes
(but the graph is the average of the reads for the minute

Cool. Thanks for the help Brian.