No, they didn't. They brought back the Start Button which takes you to the Start Screen introduced with Windows 8. Unto the topic at hand thought. To answer your question, yes I would recommend you to install Windows 8.1 as its a wast improvement to the original and a even waster improvement compared to Windows 7.
When I first switched to 8.1 I hated it for the first two days, now I like it, got used to it.. don't mind it. It's up to you really. I guess I recommend it, it's pretty neat.