I'm mostly curious what that means for something like the MIT license... For those who need a refresher, this is the part I mean.
> THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
So if someone downloaded the software from some public repository without consulting you (let alone paying you), it doesn't apply to you. I imagine that would be true if they downloaded a binary and there was no source available (so it's not open source), and it had some horrible proprietary licence that nonetheless let you use it for free.
But on the other hand, if you made them pay for some GPL'ed software and them made the source available on request as the GPL insists you must, then it does effect you despite it being open source. So really, open source and open source licences have nothing to with it.
In fact from what I can tell, part of the reason this law exists it to forbid shrink wrap licences on paid software exempting the supplier from liability. The licence having no effect on the applicability of the law is a desired feature. If the consumer paid for it, it applies no matter what your licence says.
Why this wasn't always the case is what's odd here, not this attempt to fix it.