Firefox 3.0.6 targets security issues
On Tuesday night, Mozilla Corporation released Firefox version 3.0.6, an update to its popular web browser. This version fixes several security issues with 3.0.5 and adds several functional improvements as well. According to Mozilla, the update addresses 69 bugs or enhancements,
Out of six addressed security issues, only one of the security issues was rated as “Critical.” That vulnerability (MFSA 2009-01) was caused by crashes which showed evidence of memory corruption. These crashes were often associated with running JavaScript code, not only from websites but also in email opened by Thunderbird, Mozilla’s mail client.
Two other addressed issues were rated as “High.” Issue MFSA 2009-03 addressed the possibility that an 
attacker could change a form input control type when a closed tab was restored. If the attacker knew the location of a local file, he could then gain access to the contents of that file. Issue MFSA 2009-02 addressed the potential of a chrome XBL method attack. This could result in one website’s Java code could be run in another website’s context.
Mozilla has stayed on top of needed updates since it released Firefox 3 last June. Updates have appeared approximately once a month since then.
Firefox has gone down hill the last few years in my opinion