Just as a follow-up, I think it’s important to stay current, but making a conscious effort to be trendy is a mistake.
@Sprout is correct; on a subconscious level, we’re affected by what we see around us. As people who pay attention, we take it in and combine it with what’s already there.
Quite often, I’ll find my choice of colors, typefaces, emotional tones, etc., change as I explore new ways of doing things and new ways of looking at problems. Sometimes, I’ll find other designers heading in those same directions, and in a few months, I might even read or hear about it being a trend.
It’s as though circumstances come together to make things ripe for change and a new way of looking at the world. When this happens, it’s not until after the fact that one realizes that he or she has been a part of this change. By the time it’s been recognized and identified as a trend, it’s typically already a done deal and we’re already off exploring something new.
However, this is just an observation of how my own experiences and design thought processes seem to work. I’m not suggesting that it’s something to aspire to — just the way things seem to work out with no conscious effort on my part to be trendy.
What I’m unambiguously saying is stop trying to imitate trends or you will always be a follower instead of an innovator. Also as @sprout said, the best design doesn’t focus on this sort of thing, it focuses, instead, on solving the problem at hand that the client has brought to you.
When innovation becomes part of the solution, that’s great. When a deliberate decision is made to create a trendy solution, that’s typically not so great.
When, down the road, after months have gone by, if the innovative solution you’ve created for that client seems recognizable as having been part of a trend that took place during the preceding months, chalk it up as an interesting observation.
When you notice others trying to imitate that trend, you’ll know you did something good, but, honestly, it no longer matters since all you’ve been doing all along is doing your best to solve the problem in front of you at the moment.