Lol, as if desktops will be around for the singularity.
No reason to assume they won't. There will be a lot fewer in the future, and most of the ones you will see will look like Mac minis (or thinner), but gamers, media people, and HPC are keeping the desktop form factor alive despite the dominance of laptops in the market because such people need the expandability and interchangeability of parts.
That's actually a thing that bothers me about futurists -- they have all these great ideas (arcologies, digital radio replacing analog, frequency-hopping radio broadcasts, "smart" kitchens) but they never stop to think that a) their target audience may not be interested or able to afford them or b) that they have to compete with immense installed bases for a lot of older technologies that are still perfectly suitable for their needs. After all, I could get a smart kitchen, but I don't have to worry about DRM or power outages with a cookbook. The arcology thing is another idea -- okay, which city do we tear down first? (See Boston, 1960s for what happens when people try to do ground-up urban renewal.) I mean, I can come up with a pretty good idea for what an ideal 21st century city would look like, but where would I build it, who would fund it, and how would I get people to move there in the first place?
Though I'm actually not one of the ones looking forward to it, first because it's still hypothetical and there are enormous boundaries to overcome, and second because it is inevitable that some people will still get left behind if it does happen (even if of their own volition). The divide between rich and poor is already a pain in the ass- what about a divide between immortal and mortal or physical and virtual?
See, this is why I think the Singularity fundamentally is a meaningless concept. If you want to look at a reasonable approximation of what the future might look like,
Star Trek ain't it. Think "My Life as a Teenage Robot". Think "Babylon 5". Think "Star Wars". Hell, even QC is a pretty good approximation of what the near future is likely to be like.
It's all fun and such to speculate about transhumanism, but it's meaningless to make any predictions about it without any real knowledge of how to get there. The researchers who work on things that might lead down that path are mostly doing it because it's cool, and it appears in so much SF because it's cool. The only people who treat it as Serious Business are futurists, and they're kind of dumb.