I just checked my "friend" aka DarknetGuy, describes no changes on WWDC, Mac Pro and Macbook Pro Announcement secured, also likely the all-new mac mini radically smaller and maybe more powerful.
About the next mac mini: it will be SSD-only, no spinner option, NO INTERNAL PSU, will be powered either thru USB-C Power Brick or Thru Thunderbolt/USB-C displays. The New mini look like semi-cubic about 1/3 Airport Extreme. ( I can imagine something like an intel NUC)
I Asked about a Mac Server: APPLE IS NOT DEVELOPING ANY NEW OSX SERVER HARDWARE, Apple have tested some special secured DOM that's work together TPM to enforce a tamper proof OSX Server Boot on commodity xeon server hardware (non apple), but this is an internal development, unlikely apple will sell this DOM, at least he is not aware on this, but this development exist.
About the next Mac Pro, base model may include NO ECC ram, maybe neither a Xeon cpu, no last word yet.
Apple fear weak iPhone sales, thus want to push hard on other products.