So, what do you people think? Try and solve the cursor issue or just bite the bullet and get a new iMac.
Nobody has got any idea when the new iMacs will appear - could be next week, next month, next summer. Launching new iMacs (rather than iPhones or music services) in September would be unusual, but then they just launched MacBook Pros in July so who knows?
However, more likely than not they will only be modest, incremental improvements on the current model rather than game-changers and they won't turn the 2017 models into antique curiosities overnight - personal computers just aren't moving that fast at the moment.
Further, what is almost unavoidably
certain is that not everybody will like them...
Also, price rises are not unthinkable (given that they seem to be good for the quarterly results, and those chickens won't be coming home to roost for a year or so...)
Most likely we'll see 2-core models turn to 4-core and 4-cores turn to 6-cores - which
is a useful improvement and possibly the biggest CPU boost we'll see for a while, but won't open up great vistas of hitherto unimagined possibilities. Face ID (if you see that as a plus - however, its probably more likely than TouchID on a machine with no built-in keyboard) would be slightly surprising to see in iMacs before the MBP. Smaller bezels? Maybe, but unless a bezel killed your brother then, meh.
So it really comes down to how much you
need a computer now, or whether you can afford to make do with a flakey old machine that's coming to the end of its life while you wait for news from Apple. If your wife is doing photography as a business then you should probably get a new computer
now.
...
then, try all the software fixes like PRAM resets, turning off tap-to-click, re-installing the OS or maybe, look at the
ifixit pages about replacing the trackpad (first, just check the cable hasn't worked loose, or if you don't want to pay for a replacement just disconnect it & then use a mouse). If you fix it then, bonus! you've got a spare/fallback computer. If you brick it then, well, nothing of value was lost.