These days, nearly all DVD players include MP3, VCD, CD-R/RW and DVDÂ±R/RW support. Most manufacturers still try putting these features as large clear text to make their products look like they has these features which its competitors don’t have. It’s like how new TVs advertise it is colour and comes with a remote control, composite-in, cable-ready, teletext support, etc. even though its hard to find a new TV that does not come with these features
One feature I would recommend looking out for is built-in 5.1 decoding support for both DTS and Dolby Digital surround sound support (unless you have or plan on getting a digital surround sound system).
DivX and MPEG4 support would be useful if have a CD collection of MPEG4 encoded content or plan on getting a camcorder with MPEG4 support.