Take a quick browse around Pinterest, on any particular category, and you can instantly see what the current trends are. And see exactly what is going to look dated in a few years (months?)!
Now, I really do like my Pinterest for collecting ideas and inspiration all in one place and all visually, rather than lists of favorites or bookmarks to try and sort through and remember exactly what you were trying to save...
The other day I did a search on "mantel ideas" and was amused to see that nearly every picture included a large initial/monogram, layered picture frames (filled or empty), varied heights of candles, assorted stylized flora and fauna, and chalkboards(!). Not that I'm poking fun at these ideas--I have a large "K", candles, pictures, chalkboards, and birds all on my mantel or in the same room! I just felt like I got a glimpse of what we'll be looking back at in a few years, saying, "remember when _____ was so popular?"
I really don't think there's anything wrong with being influences by others' ideas and creativity. I do think a lot of time can be wasted, and discontentment cultivated, while "getting inspired" online, and then feeling a constant need to change, redo, and "improve" on what you already have and had been enjoying! I might've been guilty of this a couple of times....or so.