Speakers with Denon 1909 suggestions

[Y2K000]

Question:

When looking for speakers does one need to pay attention to the watts of the speakers? My old speakers are 60 watts, but I been looking at bookshelf speakers and the Klipsch I noticed are only 75 watts. The model number for them are: RB-51. Also does one need to pay attention to the sensitivity level? These are rated at 92 dB. My reciever handles 90watts per channel.