Well not quite from the start, since I thought it needs 3.3V but after I switched it to 5V, it worked like a breeze. The library I used is LiquidCrystal_I2C (I found it here) - it is not compatible with Arduino 1.0 but I still have 0022 installed so no problem. Apparently, there is another library named fmalpartida/new-liquidcrystal that works with 1.0 but I haven't tried it yet - it looks like I would need to remove the library that comes with Arduino 1.0 and replace it with this one, I may try it someday.
Connecting to the Arduino is very easy:
The next step is to use this LCD with my Raspberry Pi but if I understand this correctly, the LCD working at 5V and the Pi I2C pins working at 3.3V I need to be careful, I think I will wait until this board is back in stock at Adafruit.