The best CMS is the one that works for the problem you're trying to solve. So, in essence, it really depends on the project. Just going with what's the most popular isn't the right approach. In my opinion, the most popular CMS platforms are starting to show signs of their age (ie. WordPress, Drupal, etc.). There are more modern platforms that solve problems more effectively by allowing for a more modular approach while give designers and developers far more control over the design.

That said, I have two CMS platforms that I currently use as my go-to's:

SilverStripe - A PHP-based framework that allows for scaffolding out a full data model (very similar to how Ruby on Rails works). Allows for complete freedom over the design thanks to a simplified templating model.

Statamic - A flat-file CMS (no database!) that is incredibly fast and easy to work with. Designers like it cause they don't have to know any code to build complex sites.

I tend to use SilverStripe for projects that have a lot of relational data requirements, that is where there is a lot of relationships between various bits of information. Basically, anytime where the content requirements are rather complex. SilverStripe makes it much easier to create sites with complex requirements while still making it easy for content editors to manage the content.

Statamic to me is a WordPress killer. I use it primarily for sites that would otherwise end up as WordPress sites. That said, you can do a whole lot more out of the box with Statamic than you can with WordPress. It's also much, much easier to design with thanks to a very easy to use templating system.

I'm also looking at adopting October at some point. It's built off of Laravel, which is a very modern PHP framework. My understanding is that October is highly modular and allows for a ton of flexibility under the hood. Might be good for a project or two. :)

I really think that Vista is going to be a reality check for alot of longtime Windows users. Now, to put this in perspective, I've been a longtime Windows user myself since Windows 95 first hit the market. I've used every version of Windows since then on my own desktop and have gone on to break into IT management when Windows 2000 first came out. I also broke into web development by learning ASP six years ago. So you could say that I've supported Microsoft for a very long time and have stood by them ever since....at least up until about two or three years ago! I used to swear by Microsoft. I never understood Linux; I always thought it was overly complex. I didn't get the overzealous, almost cult-like attitude of the Mac community of users. Let's face it...Windows simply dominates the desktop and it's easy to see how Microsoft can continue to hold onto their userbase.

However, with the release of Vista, I really feel that it will be very similar to what happened with Windows Millenium Edition. Starting with beta 1, I've installed and tried out each subsequent build of Vista all the way up to the latest RC1 release. All I can say is...WHAT THE?? It's a dog...a big ole' stinkin' dog! I couldn't believe the amount of resources you really need to run it. The default install is over 6 gigs, you need at least a gig of RAM just to get by, and the new interface is pointless unless you have a fairly decent video card that is DirectX 9 compatible. All in all, lots of fluff with little substance. Plus, the new User Account Control features really feel like something of an add-on...as if Microsoft just layered it on top of their existing security model leftover from Windows 2000 and XP. UAC is useless...especially when you consider that a user with administrator rights can simply disable the damn thing!

The problem is this: In order for Vista or any other future version of Windows to continue to succeed, Microsoft needs to learn that Windows needs to be rebuilt and reworked with a new security model that rivals even Unix-based operating systems. Nobody can say that Unix, Linux, and even Mac OS X are bad operating systems when it comes to security. They are very secure by their very nature on how they were built. Microsoft needs to learn from this and build on top of it. This is why Apple made such a smart move when they developed OS X. Rather than re-inventing the wheel, they simply took a proven secure OS and built on top of it. The beauty behind this is that the OS is modular and can be easily updated and upgraded. Windows is anything but modular.

I've since moved on from ASP and am now using PHP as my web development platform of choice. Naturally, I use Linux as a server platform and plan to use a Mac as a desktop. I'm simply tired of Microsoft and all their shenanigans. At least with Apple, when they say their going to do something they do it! They don't tease their customers with features and then pull them out later and say, "Sorry! We screwed up!" So, make mine Apple! I'm really looking forward to Leopard! :)