For me web safe color palette is no longer primary concern. Optimize for the largest target audience.
According to w3schools site visitors:
- In January 2009 1% of site visitors had 256 color displays, 95% of users had
24 or 32 bit. - [Update] In January 2015 0.5% had 256 colours, 0.5% had 24 bit and 99% had 32 bit
I found similar numbers from a business app site that I look after:
32-bit 79.01%
24-bit 15.64%
16-bit 5.27%
8-bit 0.08%