NORIKER  Regarding my recent review, the developer has announced that both said problems (searching in German and searching for plural) will be fixed.  
(Version 3.1.1)

NORIKER  Jisho comes in very handy if you're a user of Quicksilver because it adds a Services entry, that you can call from QS (Period; enter Search Term, Tab, Jisho).

I also find it interesting that it (theoretically) understands various languages. Unfortunately it doesn't actually work unless you use the "broad" or "extra broad" settings, and everytime you close the app, it forgets the settings. But for English it's ok.

What I don't like at all, is that it doesn't allow searching for any plural forms, only for singular, as there is no plural form in Japanese (which doesn't mean you can't just translate it to the singular). This again makes it impossible to quickly search with Jisho if you select a plural in Text Edit or Safari and want to use Serives or Quicksilver to find the Japanese translation. I already mailed the creator about it but he doesn't want to change it.  
(Version 3.1.1)

STORMCHILD  It's nice to see alternatives being developed, but JEDict is still the king, and the built-in Japanese dictionaries in OS X are quite good too.  
(Version 3.0)

SNOWLPRD  Apps such as this one are less necessary now that Leopard includes a Japanese-English dictionary [link].  
(Version 2.2)

HYPERFRANK  If you are looking for a free alternative to Jisho, see Wisho (http://homepage.mac.com/domg/FileSharing2.html), a free and excellent widget that uses EDICT as a database.   
(Version 1.3)

BEN   If you are like me and did not like the user interface of Jisho 1.0 you should give Jisho 1.2 a try. The user interface has been totally redone and is much more user friendly. Searches seem to be remarkably faster than previous versions and the added languages are also a bonus.

Over all it is a nifty little program that can come in quite handy if you a struggling with a new language and are not quite sure of a translation. I like the added German and Russian languages, as those are the ones I am most likely to use. $10.00 US is a small price to pay to help out a developer and I am looking forward to future updates of Jisho.  
(Version 1.2)

RASKOLNIKOV  Mayjay is very good, it is based on edict too,

and lets you search with wildcards (*), meaning if you know one of a two or three kanji word you can find them easily.  
(Version 1.2)

MINTMUFFIN87  It desplays no kanji and just one meaning for each root.

If you want a free japanese/english dictionary for Macintosh displaying Kanji, download Akane at this URL http://ftp.cc.monash.edu.au/pub/nihongo/AKANE.1.0.3.sit.hqx,

which I found here: http://ftp.cc.monash.edu.au/pub/nihongo/00INDEX.html.  
(Version 1.0.1)

ANONYMOUS  not worth 10$ should be free. Using the EDICT file anyways.. those who want a good EDICT dictionary online with tons of info and kanji

http://kanjidict.stc.cx/dict  
(Version 1.0.1)

TODD FIASKY  i dont know how many people noticed, but the pic on the main page has AIJOU as AIPYOU for the conversion. hmmm.. seems sketchy to me

also, there is no kata input, no kanji input. I really don't see this as a useful application unless youre some kinda anime nerd  
(Version 1.0.1)

ARNDT GERZ  Just had a quick look at the capability of Jisho 1.0.1. As long as the 'tsu' sound in the Japanese language (examples in my first trials) is shown correctly with the hiragana/katakana symbol, but is shown in Romaji as 'zu', this will be a failure for all native English speakers who wish to learn the proper pronunciation from Jisho. The hard 'ts' reading for 'z' will be more familiar to those schooled in other European languages, but native English speakers will naturely want to say a soft 'z', and the 'zu' indicated in the Romaji listings are incorrect! Have not tested other potentially 'sensitive' vocabulary yet; I hope this is not an indication of what else I might discover (I purchased Jisho before testing it!   
(Version 1.0.1)

CHRIS  Pretty cool stuff. Very pretty. :)  
(Version 1.0.1)

LUKAS  It seems to be a little buggy at the moment. The "Look Up" button flickers and the roma-ji transcription is a little off (it includes the small 'tsu' character instead of repeating the consonant ['bokken' is written as 'botsuken']. Seems viable in the future, but Mayjay is open source, freeware, and works great.

http://www.ziggr.com/mayjay/  
(Version 1.0)

CHRIS JENSEN  Wow, this is a really nifty program. Simple to use, fast and clean. I can't wait to see the features they add with new versions. tanoshimu! :)  
(Version 1.0)