IAIAN7  Historically, the Last.FM player has been inconsistent and unreliable, rarely doing correctly what it claims to do (especially iPod based scrobbling).

However, with the updates made to iTunes in summer 2009, Last.FM can actually crash the entire music system. Just to enable syncing with my iPhone, I had to completely wipe Last.FM from my system; the iTunes plugin, the application itself, and its preferences.

Not just a bad-but-usable application anymore, it's downright malicious. Please avoid if you wish to continue using iTunes+iPod/iPhone.  
(Version 1.5.4.24670)

LOCH_RAVEN  this program is really obnoxious. somehow it makes itself a startup item. even when i remove it from the startup list it somehow re-adds itself! so irritating!  
(Version 1.5.3.45507)

AMUZAC  New version seems to work properly under Leopard.  
(Version 1.4.1.57486)

LUX  No problems in Tiger but I can't get this to work properly in Leopard.   
(Version 1.3.2.13)

THREEDEE912  Perhaps you should look into iScrobbler, which is an alternate Last.FM client. It doesn't have Radio though.  
(Version 1.3.2.11)

KLKTRK  I like the last.fm Web site, and I love the idea behind this community/app.

However, I think the developers should know that even when the Last.fm application is only scrobbling (ie *NOT* playing music, but rather only scrobbling what iTunes is playing, it hogs 40-70% of my processor at all times. Compare this to iTunes, which, while actually playing mp3s is only using 5% of the processor. There's something wrong with this app's code. Are the developers even running it through Shark or any other code analysis tools?

Again, I love the concept, but whenever I have last.fm running, it slows the computer to a crawl.

2 GHz PowerPC G5 with 1Gb of Ram, running Mac OS !0.4.10  
(Version 1.1.3)

GLOBETROTTERDK  Earlier versions of the player tried to scrobble in all sorts of places I told it not to. Now with verion 1.3.0.58 I get the message "Won't scrobble: track is in a directory set to not srobble.

I really like the idea of the site, but there is a lot of work that needs to be done on the app.  
(Version 1.1.3)

GLOBETROTTERDK  Last.fm Player is now at version 1.3.0.58 Go to the Last.fm site and download the player there.  
(Version 1.1.3)

MIKEJENKINS_UK  Make sure iTunes is closed when running this app for the first time, or it will almost immediately crash.  
(Version 1.0.6)