Regarding next year's Miku concert, SEGA has already announced that there will be two concerts held on consecutive days in Tokyo Dome City Hall. Next year, SEGA will be collaborating with MAGES (5pb) to hold the concerts on 8th and 9th March 2011. There will be afternoon and evening concert on both days. On the first day will be a Miku Live Party (Mikupa) 2012 live show and on the second day there will be a Miku's Thanksgiving Day live show. The two concerts will open at 01:00 PM and start at 02:00 PM for the afternoon live show and for the evening show it will open at 06:00 PM and start at 07:00 PM.
The ticket costs for 6300 JPY each concert. Ticket sales will begin on 28th January 2012 at 10:00 AM (Japan Time). There will also be a web raffle to win tickets for free starting on 23rd November at 12:00, and will be end on 12th December at 09:00 PM.
It is still unclear if the concert will be 100% new or just recycling the old ones. And it is still unknown if they will stream it live via Nico Nico Douga or not.
Here's theofficial video that SEGA has released. Enjoy!
Source: SEGA Project Diva Blog, Official 39's Giving Day Website.