Until now, the lower price offered by the Keisei Line Skyliner was tempting (¥ 2,400 including the reserved seat), although the comfort is a bit lower compared to the JR East Narita Express (¥ 3,140 including the reserved seat) and the final station is Ueno.
Today, the new JR East promotion is changing the balance: starting January 10, the JR Narita Express ticket to Tokyo will cost only ¥ 1,500. But note that the offer is only available for the Narita Airport - Tokyo direction and only for the foreign tourists...
EXIF info:
Nikon D90
Lens: 18-70mm F/3.5-4.5G
Focal Length: 18mm
Aperture: F/5.6
Shutter Speed: 1/400s
ISO Sensitivity: ISO 200