Things to do in Osaka and Tokyo

My friends and I will be going to Japan end of this year.. and we'll be in Kyoto for Christmas and Osaka on Christmas Eve. Since we'll only be in Osaka for 1 day, are there any places that we must absolutely visit?

Also, we will be in Tokyo over new years (30th Dec - 4th Dec). Are there any recommendations on what to do over the new years eve and new years day (other than visiting shrines)? Are there any countdown parties or concerts that we can go to? And finally, we are planning to to a day trip (each) to Hakone and Nikko from Tokyo on the 2nd and 3rd Jan, will most tourist sites be open then?

We're open for any suggestions.. so any advice would be greatly appreciated. Thanks!

Please enter you frequently often asked questions in the small search window right above the list of all the questions in the forum opening page. You will get a whole bunch of previous posts on these subjects. I have been to Osaka 6 times, for several days each time, and haven't seen even 1/4 of Osaka.