I have been using Arduino to build many electronics projects listed in Sparkfun's starter kit Thanks to the kit, I have been able to easily build absolutely awesome things as a begineer. Within two nights of work, I already learned to combine different kinds of sensors (temperature, light, physical contacts) with actuators (motors, speakers, LED lights) and IC chips. So I love my Arduino with a starter kit which you can see in this photo.
But now I ask: if I were given a choice between Arduino and Raspberry pi to build electronic devices, what would I choose? Without delay, I would go for Raspberry Pi. For about the same price ($35) as Arduino Uno board R3 ($25), I can get a whole linux computer that can digitally control all the circuits listed in the Sparkfun's kit. Contrary to Arduino, it can do Internet, play TV through HDMI cable, and save data through miniSD chip.See the diagram indicating all the awesome stuffs that can be done with Raspberry Pi!
Ahhh go for Raspberry Pi even for amateur electronics projects.