22 Sep 2012 - 7 Oct 2012 high tourist season visiting South Korea ?

I wasn't aware that Korea was huge draw for Chinese tourists. For those dates, I'd be far more concerned about Cheosok, which tends to cause quite a bit of havok if you're trying to travel around the country.

That said, I was in Seoul over Cheosok 2 years ago, and it was a sheer pleasure. The city was almost empty.

how bad was it during Cheosok? do you mean price of accommodation and transportation will be going up ?

I never left Seoul during Cheosok, but from what I've heard, its quite a mess. The roads are jammed with people going/coming from all corners of the country.

I never found the cost of anything to be an issue. Most people are visiting relatives, not staying in hotels or going to restaurants, so if anything, it might be cheaper.

chusek is korean traditional holliday season from 29 Sep to 3 Oct.
Most of people living in seoul will go to their hometown.
So, If I were you, I would stay in Seoul during that season.
on the other hands, during that season, you can enjoy sightseeing Seoul/Kyoung gi province more easily.

in term of weather

It's my favorite time of year for the weather in Korea. You should expect plenty of clear, sunny days, and warm temperatures (daytime highs of 21-27C/70-80F and cool evenings/nights).

The price of accomodation is not bad because most Korean tend to stay their parent's house.
But, If you would go to other country besides Seoul, Kyonggi you could meet traffic jam.
However, I think you don't need to worry about that.

Hi Jay,

My trip to Korean happens to coincide with Cheosok as well.

Will the shops like traditional markets or places of interest be closed for the Cheosok holidays?

I didn't notice anything closed on Cheosok when I was in Seoul. All the big attractions (palaces, shrines, etc) were open.

Thank you, netllama. That's good to know.