"Upgrade" from 8vCPUs to 2?
I don't know if it's right but it's trying to "trade" more ram, bandwith and storage for -6 vCPUs?~~
You do get fewer CPUs, but because of the speed of the SSDs and the faster servers your processes execute and complete faster (so having fewer CPUs isn't a problem for most users). If you were comfortably using a 1GB server without performance issues then you probably weren't utilizing many of the available CPUs.
That said, Linode doesn't (seem to) really care if you max out your CPUs, so if you are CPU-intensive in what you are doing, it shouldn't be a problem.
It would be nice to have a notice along the update with something like "new SSD and CPUs infrastructure, more information here".