In the latest update (10.1.2), you can no longer do ctrl+alt+space and type the name of an application. In stead, it opens one of the buttons on the right, depending on the keys you happen to hit. Type "th" for thunderbird and the help-button is "clicked".
It was hopelessly broken for a large percentage of users, so it now requires you to type / or F3 to trigger it. This is mentioned in the 10.1 release announcement right in the first paragraph and on the features page. We'll likely be adding in an always-visible search box in the near future that will support it properly.
Sometimes, the impossible can become possible, if you're awesome!
I quickly picked up on using "/" to make the search field visible after the launcher menu is up however it's a noticeable productivity hit if your workflow means you're in and out of apps often.
It would be nice to have the option to enable the broken way under the settings so that the people who use it heavily could still use the old keyboard launch style until the definitive replacement is ready.