Fire up Software Update and you’ll spot a new addition waiting to be donwloaded: 10.5.4.

Updates seem to include Airport, iCal and Safari fixes along with general security improvements. The full list of updates is below, or the relevant page on the Apple web site is here.

I’m still on 10.5.2 so I’m starting to lag behind the times somewhat. If you update be sure to let us know if there’s anything we should know about, like it breaking stuff that already works !

UPDATE:

What did I say? Let us know if it breaks something. Sure enough, Justin’s Mail icon’s gone walkabout:

Anyone else having this, or is it just him? Let us know in the comments section !