Will there ever be faster CD and DVD discs and writers?

It's mostly a technical limitation. Put simply, if you spin the disk too fast it starts to become unstable and wobble around or even start to come apart under the sheer stress. At best this means read/write errors - and at worse means the possibility of it coming loose and causing damage.

At 52x speed, the disk is spinning at around 24000 RPM - at around 27000 RPM the disk would start to crack.

KenWood has played with CD-ROMs that use multiple lasers to read several places on the disc at once and then re-compose them into a single stream in firmware. They call this technology TrueX. You're able to read data faster at the same spin rate, but you need to use a more powerful laser (since it's being split), which requires more power and results in more heat.

About a decade ago there were CD drives that used multiple laser beams to read 7 tracks at once for higher performance without having to spin the disk extremely fast. However they were expensive and apparently had reliability problems as well.

It's also worth noting that it isn't just a question of structural integrity of the disk at high RPMs, but also of noise.