I returned to formal piano lessons in 2005. I had played at school (but that was in the early 80s and my teacher never actually did any of the formal stuff scales, sight reading etc) so I am not the lessons really count!
At university (in the early 90s) I got into synths and MIDI sequencing and I have slowly moved towards wanting to actually learn to read the dots and all the formal stuff.
I took grade 4 piano in Mar 2006; passed grade 5 Dec 2006 (only just!); Grade 5 theory in Jun 2007 and then Grade 6 piano in Dec 2007.
I have set myself the task of passing grade 7 & 8 piano in the next few years, and hopefully theory grades 6,7,8 as well. Fun!
I am currently in Japan for a year (with the family) and trying to find a piano teacher before my level slips too much!