Happy New Year 2012

In present-day Japan, they celebrate the solar new year on January 1st, but they associate the new year with the symbol of the upcoming Chinese lunar year, which begins later. 

2012, then, is the Year of the Dragon, and this is the dragon Kanji (Chinese character).

Before the new year begins, the greeting is

"Yoi otoshi o omukae kudasai"

which is wishes for a good year.

よいお年をお迎えください。

or informally "Yoi otoshi o."

よいお年を！

After the new year begins, the greeting is

"Akemashite omedetou gozaimasu"

明けまして
おめでとう
ございます。

One blog translates this roughly
 "The year is changing...
darkness gives way to light...
new life begins...
Congratulations!"
I really like that.

or "Shinnen akemashite omedetou gozaimasu."

新年 あけまして
おめでとうございます。
 
In writing, Happy New Year is often given as

"Kinga Shinnen."

謹賀新年

In Japan, the custom is to write New Year's Greeting cards.

A phrase such as "Sakunen wa taihen osewa ni nari
arigatou gozaimashita," which means
"Thank you for all your kind help during
the past year" is a common text.

昨年は大変お世話になり

ありがとうございました｡

or "Honnen mo douzo yoroshiku onegaishimasu"

(I hope for your continued favor this year.)

本年もどうぞよろしくお願いします｡

My wish for all of you in my virtual New Year card is this:

"Minasama no gokenkou o oinori moushiagemasu"

(Wishing everyone good health.)

皆様のご健康をお祈り申し上げます｡

For more Japanese words and expressions, check out this blog.