New MacBook Pros:
- Thunderbolt: The actual highlight of the introductions. Macs finally have a high-speed connector that is (more than) competitive with USB3.
- Updated processors, quad-core on 15" and 17" models.
- Faster RAM, 4GB
- FaceTime HD camera: “three times the resolution of the previous camera”.
- SDXC card slot: greater capacity, faster.
- Graphics: integrated Intel HD Graphics 3000 processor.
- 15", 17": additional AMD Radeon graphics processor, to be switched on when more processing power is needed.
- Screen resolutions: unchanged. Notably, the 13" MacBook Pro only has 1280 x 800 pixels, while the 13" MacBook Air has 1440 x 900.
- Battery: On paper, batteries last shorter. “All models now feature a battery that Apple said provides 7 hours of power between charges, down from the 10 hours it boasted for last year's 13-in. MacBook Pros and off the 8-to-9 hours estimated for 2010's larger 15-in. and 17-in. models. Gottheil, however, said that the changes in battery life estimates resulted from a new, more rigorous testing procedure that Apple is now using, and dismissed the idea that the new processors and graphics were behind the battery declines.” 
- Other details (weight, prices): mostly unchanged.
- Already known: Mac App Store, Launchpad, Full-screen apps (no menu bar!), Mission Control.
- Auto Save: applications auto-save documents, with past versions stored inside a document. It’ll be interesting to see how this interacts with Time Machine.
- Versions: Visit past versions of your document with a Time-Machine-like user interface. Time Machine currently supports this in Finder, Mail, Address Book.
- Resume: Remember open documents and window positions when quitting an application, remember open apps when rebooting or switching off.
- Mail 5: Window is split horizontally, which better supports widescreen displays. Support for “Conversations” (threads).
- AirDrop: Use Bonjour to discover people in your environment that you want to share files with.
- Always comes with server functionality. Not clear if this means that there won’t be a server version, any more.
- Facetime now costs $0.99 in the Mac App Store. Why charge for it? It just makes Apple look cheap. Apple says that the charge is necessary because of “accounting requirements”. Shouldn’t there be a way around this kind of thing?
- Thunderbolt – signs of things to come: Apple mentions that “With PCI Express technology, you can use existing USB and FireWire peripherals — even connect to Gigabit Ethernet and Fibre Channel networks — using simple adapters.” Apart from Fibre Channel, current MacBooks don’t need this functionality. So it’s an indication of what’s to come, at least for the MacBook Air (as if you had any doubt...).
- Apple boosts MacBook Pro speeds in 'ho-hum' refresh
- Thunderbolt (code-named Light Peak): an overview
- Update: Mac OS X Lion Building in Support for Super High Resolution 'Retina' Monitors
“These HiDPI modes allow developers to supply 2x-enlarged images to support double-high resolution displays. [...] This new system seems far easier to support than the previous system which tried to support an arbitrary number of resolutions with elements described in vectors or multiple bitmaps.”
- Update: What we know about Mac OS X Lion
Noteworthy: Mail.app conversations are like GMail’s, but don’t include sent emails. Rewritten Finder that can group by file type. iPad-style user interface tweaks for several apps. Speculation that iOS and Mac OS user interfaces and apps will eventually merge.