I used to feel like good design had to have a sans-serif or better yet, a condensed, bold sans-serif. It looked modern, clean but also strong and filled up the page with a lovely dark element to contrast the white space. Now, the wonderful trend has been towards a small touch of a script typeface in combination with a slab-serif. Sometimes they are used together and sometimes individually, but either way, the design trend is refreshing.
Script typefaces (I happen to be a sucker for anything hand-drawn as well) can be sophisticated, modern, smooth and adds a touch of individuality to a design.
Script typefaces also remind modern designs of something traditional which I love to see as a designer. As technology becomes more and more prevalent, these small touches of curves and flourishes keep the communication pieces special and more targeted in their approach.
Slab-serifs have a completely different feel. They are stronger, bolder and offer a lot of structure to a design. They also are great to use to stack and line up elements. The right ones can have a very indie vibe to them and seem to work in combination with script and light typefaces. Overall, they are a versatile choice for an identity design or headline.
One thing is for certain, typefaces go through trends and the minute you pick up on one, another one becomes popular. Scripts and slab-serifs are very popular now, but in my design heart, they will always have their perfect use and place in the right communication piece.