I am having trouble w/ k2 component in backend, since when I hit the save button, I have to wait 2min (or more) to succesfully save whatever (article, category edit etc.). Is it a bug, (or a feature? :) )

Neither actually.

This is something you address to your host however.
I could be a lack of memory, cpu limits etc.

Thanks for response. I did contacted my host server, actually they've said it is joomla component, since all other components and joomla article component works fast and easy. So, any idea what to do? I have about 500 articles uploaded to k2 component, and I do not want to rewrite them back to joomla article component again...

@martin viglas

K2 performs far better than other components, especially the core Articles component. The time K2 needs to save an item depends on many factors:

1. File uploads. If you are adding an image, a video or attachments to K2 it will need some time to upload those files. The time depends on the files size and your network speed ( assuming that your server is working fine ).

2. Look for any K2 plugins hooked in the item form. It might be a third-party plugin that performs some time consuming tasks.

Of course i assume that you use the latest version of K2 and Joomla!.

I've seen some posts before I have post mine, and -
the joomla and k2 comp are the actual release (latest versions avaliable)
I have no other k2 plugins installed,
I was not uploading anything (since I've been just changing category presets)
any idea of what is wrong?
thanks a lot.

No, i don't have other ideas. Try to create a new item. Just enter a title, select a category and click save. If you don't have any K2 plugins installed it should be saved within a few seconds. Check also for third-part content plugins in your system.