When Leopard came out, I was very excited about the screen sharing feature. I thought I'd buy the OS in Jan 2008 for that feature alone, but there were so many bugs I waited until Sept 2008 to update my main machine.
During that long wait there was great excitement about how useful Screen Sharing in Leopard 10.5 was.
Actually, there was total silence. A very suspicious total silence.
Which made it easier for me to wait until 10.5 was halfway decent; I knew my original expectations wouldn't be met.
Today, with both the MacBook and iMac running 10.5, I launched my long delayed test. It took about five minutes to make the call.
I'll keep it short. Leopard's VNC-based screen sharing is a toy compared to Citrix or Microsoft Remote Desktop.
Yes, it's marginally better than the worthless VNC tools I've previously used on OS X, but only someone who'd never used Citrix or Remote Desktop could think this imagine this VNC based solution was in any way comparable.
It is suitable only for use with iChat to do remote debugging, or with 'back to your desktop' to retrieve little fragments of data.
Typing lag is intolerable. The "scaling" is bitmap, not vector. There's no automatic vector resolution matches to the current display (which Microsoft has done for about 10 years).
The remote window is hemmed by the usual OS X chrome, so the usable screen space is very small. Keystrokes are not adequately captured; for example, I can't run LaunchBar on the remote display as the the local app captures my keystrokes.
Apple once marketed screen sharing as the #4 feature in Leopard, a few steps behind Time Machine (which has so far been of no use to me). Clearly Leopard was not about providing new features to users -- it was really about moving the development platform along.
OS X 10.5 was originally supposed to have a scalable Quartz-based UI with (screen) resolution independence. I can imagine that there was a screen sharing solution that went with that scalable UI, and that it was a serious Citrix/RDP competitor. Apple pulled the scalable UI before 10.5 was released; given how troubled 10.5 was, we know they made the right decision. Maybe, after the scalable UI was lost, Apple jammed this VNC solution in to fill the hole.
I'm sure I'll find a few uses for it, but nothing like what I was hoping for.
Update 9/27/08: BTW, you can only connect to the current user session. If it were possible to connect to a background session I'd have given screen sharing some points. It's obvious by the lack of objection to Apple's marketing that this is one of those capabilities that the vast majority of users really don't need or want!