The funny thing about that is that the Playstation originated as a CD-ROM add-on for the SNES (srsly, look up SNES-CD on wikipedia). Some stuff happened, Nintendo wasn't really into it, and Sony decided to go ahead with it on their own. So we have Nintendo to thank for arguably one of the greatest brands in gaming history.
And I too thought Playstation was a silly name for a console when I first heard it. But not as silly as "Xbox". Just goes to show, you can get used to near any name. Regardless of how silly it may sound at first.