OK, the last one was a failure.  I have been walking a lot more recently, especially over the last year, but it's not enough for various reasons.  So the Challenge has been reset, with a few tweaks.
From 1st June 2013 to 31st August 2014, I will try to do 120 walks, 1000 miles and 40000 metres of ascent.   I will also spend 60 nights under canvas, tent, bivvy, bothy, etc.
Basic rules -
 - Minimum walk is 3 miles, anything less is just a stroll.
 - No walks to the shops, etc. are counted.
 - Walks to be predominately in the countryside/off road. i.e footpaths, bridleways, country lanes.
 - I choose whatever walks I want, no restrictions on doing the same route over and over (would get boring mind!).
 - I can do as many separate walks in a day as I want (though they have to be separate, not before and after McD's...)
 - Long distance trails counts as multiple walks (4 day LDT = 4 walks).
 - To count I must do a trip report/blog (Unless I'm doing the same walk over and over...).
 - Mileages and ascent taken from GPS/Getamap/bikehike or the best I can calculate if abroad.
The basic rational is that I'm doing (if I walk enough) a big trek in September 2014, so I have 15 months.  I want to walk on average 8 walks a month (which is just less than the last challenge, but more likely to happen).  I have upped the average mileage to 8 miles and upped the ascent to 300m.
8 walks a month, over 15 months = 120 walks
8 miles average a walk = 960 miles (close enough to a 1000, to make it a nicer number!).
300m average a walk = 36000 metres (again its close enough to round up to 40,000).
So that's the plan! The numbers are big, but If I get ahead in the summer, I have a chance to keep it up over winter.