i have seen many different things on the internet about weather seasons in SE Asia. I am planning a trip in or around Jan 2010 and previously I was thinking about either Thailand or Indonesia. Now I checked out the weather seasons for both areas, and Indonesia seems to be in wet season during that time, but Thailand is dry...but then another site says, the further south you go, the less "wet" there is during wet season. Is this correct? Does it make sense to even consider a beach/cultural exploration trip in january to indonesia? Should I only consider Thailand for that period during the year?

Here's an article on our Bali travel guide from January of this year.

And more information about weather in Bali here. Other parts of Indonesia may be slightly different, depending if you'll be in coastal areas or mountains. But you can probably bank on it being largely the same - wet.

As a general rule, most of SE Asia is in its dry season November to around April time with the exception of northern Vietnam around xmas time and Indonesia which seems to have its summer the same time as Europe and the US.

That is incorrect that most of SE Asia is its dry season from Nov - April.

Indonesia, Singapore, Malaysia, and even the Philippines experiences wet season during this time. As well, there is another shorter period of wet season during June - July.

Although do understand that wet season doesn't mean constant rain around the clock. Yes, it's more likely to rain, etc.. but often enough, it's for short bursts (although yes, it depends where you are). Beach in Indonesia around January should be fine, as long as you understand that the waves would be stronger, etc.. (depending on some parts).

Not all of Southeast Asia is the same, including the weather. You'd understand it better once you arrive and see what 'wet season' means depending where you are.