Bill,
regarding what about the Ortofon A90 that is new technology;
the body of the A90 is built with a process called Selective Laser Melting (SLM) in which micro-particles are laser welded together layer by layer. similar to the reconstruction sequence in the movie '5th Element'. say what you want about the cartridge; certainly no other phono cartridge is built with technology as new and inovative remotely approaching this one.
here is a
link to some details.
my favorite cartridge at the moment is the Lyra Olympos SL. there are a number of other great cartridges out there i've not heard or spent enough time with to say what's the best or anything like that. but the A90 is a special cartridge which seems to work in many arms and systems.
i certainly agree with comments regarding improving tt's and arms and even phono stages, as well as set-up precision as sometimes/mostimes making more sense than cartridges. i have 3 tt's and 4 arms and 2 phono stages. context can be everything to cartridge performance. yet no doubt the A90 seems to stand up in pretty much any context as special.