MARUKO DRINKING TEAM  This is, when fully working, the very best SVN client on any platform. I also use Versions, which is pretty good. Cornerstone is better, though; more features, and better UI.

The problem with Cornerstone is that it lags woefully behind critical updates sometimes. I had to work with some svn 1.6 working copies (1.6 changed the format again), and it took MONTHS for Cornerstone to be updated for compatibility. Here, I see users complaining of the same thing with the Mac OS X 10.6 update.

So, I think this is some really good software that suffers from product management problems (or perhaps the developer is just too small to keep up with the outside world in a timely manner). Unfortunately, that means there are significant stretches of time that the app is basically useless.  
(Version 1.5.2.18)

LOERIBAS  The one thing I missed on the Mac was a good svn client like Tortoise on the pc. I've tried several clients for Mac but they all fall far behind Tortoise.

Then I found Cornerstone.

It's at least as good as Tortoise and much more fun to use! A very 'Mac like' application. The best OS X svn client.  
(Version 1.5.2.18)

ICONZ113  great application, far exceeded my expectations. I can also vouch for great customer support.  
(Version 1.5.1.17)

SHOCK J  Hadn't seen an update for this app in a while. I thought the developers might have been slacking off, but looking at the new release notes nothing could be further from the truth. There is a HUGE laundry list of changes and improvements. Glad to see this app has gotten some major attention.

I due have to question the lateness of this release though, as the product was completely broken under Snow Leopard (would not launch), leaving it's user base completely in the cold for a full month. That's a long time to leave your users high and dry. I’m sure some people chose to move on the alternative applications. I did. But looking at all the improvements, I'll certainly go back and give Cornerstone another look.  
(Version 1.5.0.16)

SHOCK J  Will not launch under Snow Leopard. PLEASE FIX.  
(Version 1.1.7.23)

MONOT  Even though it's a bit more expensive than the Versions, I like the Cornerstone much better than the Versions or other SVN clients. Maybe, the Versions is a good tool for non-developers who just need to do version control in their project, but definitely this one is for developers (and of course, for non-developers).   
(Version 1.1.4.20)

BNZ  Too expensive. I won't ever consider buying such a tool at this price point. I find $15-$20 is more appropriate for such a tool.  
(Version 1.1.2.18)

SHOCK J  Is it just me or is the application slow as molasses when it comes to updating/refreshing views. SmartSVN doesn't have nearly as clean an interface but at least I don't spend half my time waiting for the view to update. When this things get about 10x faster, I'm all over it.  
(Version 1.0.2.59)

EGN  The app is excellent but the best part is the support. I've had lots of questions and they have all been answered in a timely and very generous manner.  
(Version 1.0.2.59)

VDANEN  I'm using it with svn+ssh right now and it works just fine.  
(Version 1.0.2.59)

JACKSIMJACK  Very nice and usable UI, great feature set.  
(Version 1.0.1.58)

NECRISREX1  This looks nice but until it supports svn+ssh properly I can't use it.  
(Version 1.0.0.57)