I'll try to keep this post updated with 2010 slogans for each team.
(I also do realize that Tatsunori Hara mentioned that he wanted to use the same team slogan as last season, but it has not been officially posted by the Giants as of yet.)
|Yakult Swallows||JUST PLAY TO WIN||1/21/2010|
|Yokohama Bay Stars||フルシーズンフルパワー、アナライジングベースボール||1/20/2010|
|Rakuten Eagles||Ｓｍａｒｔ ＆ Ｓｐｉｒｉｔ ２０１０ Ｅａｇｌｅ Ｆｉｒｅ！||1/18/2010|
|Yomiuri Giants||Ｓｈｏｗ ｔｈｅ Ｓｐｉｒｉｔ～原点～||1/14/2010|
|Chiba Lotte Marines||和||1/12/2010|
|Nippon Ham Fighters||Feel it!||1/5/2010|
|Seibu Lions||No Limit! 2010 逆襲の獅子||1/5/2010|
Not really a team slogan, but the NPB announced on 3/11 that their slogan for their Green Baseball Project was going to be ＬＥＴ’Ｓ省ＴＩＭＥ！ It's actually a play on words as the kanji character "省" is read sho, or show. In Japanese, the kanji character is actually from the word 省エネルギー, which means energy conservation.
The official NPB slogan was announced on 3/16 as 「ここに、世界一がある。」