sadly, WL Domains is pathetic in comparison to Google Apps. I signed one of my spare domains up for it to see how competitive it is, was disappointed.
This is literally all the domain settings you have - that is to say, none:
There is only one MX record you can add to direct mail to WL, unlike Google's handful of alternate records.
Although, to be fair, it looks like this is a user-customized record tied to you (which would explain why it doubles as a domain-ownership verification), so it's almost certainly just a public-facing dummy that's routed to a number of different servers (then again, Google probably does the same with every single one of their alternate addresses).
Custom Addresses let's you CNAME a subdomain for the mail address, like mail.yourdomain.com, nothing special, GApps has it.
This is the member accounts page:
The add an account dialogue is basically the same as the edit account dialogue. What you see are the only account management options you have. No aliases, force SSL, 2 factor auth, Contact sharing, Labs, nothing.
Open membership lets the public sign up for accounts directly, I think this Google Apps doesn't have, but it's not very useful for a personal domain. Co-branding, as the name suggests, lets you personalize some stuff.
And that is everything there is. When you first sign up it defaults to the old WL Hotmail but (fortunately) you can easily switch to Outlook like any other Hotmail account.
Google Apps is a far more mature product, and some of its business-orientedness shows in its features, like Group management, detailed feature management, permissions management, even advanced settings like DKIM signing (which I've enabled).
Other Google Apps features that are really useful include being tied into all the Google services that you've come to rely on, like Calendar, Docs (I guess it's called Drive now), Webmaster Tools, Analytics, etc..
Right now Google Apps is simply the most feature-rich hosted mail offering there is, and that's not even counting the enormous advantage that **********ing Gmail already gives it. No other service provider I've seen, for example, has DKIM signing, or such granular control of such a wide variety of services, even the paid ones.
I signed up right at the start so I was grandfathered into the original plan, there's still a form I could use to request more users, I don't know if they'll actually honour it though as I've never had a need for more than my existing quota. The only thing that Google Apps is missing is the ability to change the primary domain - and this is probably intentional since they want to wean people off the grandfathered plans if we need to switch primary domains for whatever reason.
I've been looking for a Google Apps alternative for a long time, due to concerns about data privacy, but unfortunately there really isn't a good alternative. Hopefully them going paid will give some others a fighting chance, I'd even pay a nominal sum for a good email service hosted outside the US, but that just doesn't seem to exist at the moment.