Version 1.0.0RC3 was just released this morning for Slic3r. There are several major bug fixes in this released. Here is the complete list of fixes:

Bugfixes:
- facets were completely reversed because of an overflow triggered by STL files with very large coordinates
- rectilinear infill was exceeding perimeters when using very low layer height
- random lack of infill caused by recent changes aimed at reducing memory usage
- incorrect number of raft layers was geenrated when too few were requested
- fatal error in the rare case that a bridge has no valid anchor points
- fatal error when concentric infill generated too tight loops
- spiral vase generated some wrong layers
- when processing with fill_density = 0, top/bottom solid shells were missing regions thinner than three times the extrusion width
- the M73 command used with makerware/sailfish G-code flavor exceeded 100% under certain circumstances

Download here: http://slic3r.org/download