The slots thing is a design decision. Apple doesn't think people need them, I think they may be right. The Thunderbolt connectors are direct to CPU, not even the north-bridge in the way.

I remember when they said people wouldn't need ADB or SCSI. Or floppies. Or serial ports. It worked out.

If your 5 GHz CPU a Xeon with ECC? The RAM can be upgraded (those are options), the SSD can be upgraded (1 TB is an option) and it's faster than SATA, and you can attach as many disks as you want in Thunderbolt arrays. Did you have dual GPUs for that price?

It's a nice looking machine, very quiet, and very innovative. Maybe it will be a misstep, but I'm glad Apple is trying something interesting. I want to see what happens with this.