The plan I am following is a combination of the Runners World 3:15 plan and the 3:30 plan. The 3:15 plan is the main one I follow in terms of activities, distance, etc but where the times are somewhere between the two. For example if the 3:15 plan says to do 1 mile 'intervals' in 6 minute mile and the 3:30 plan says to do the same in 7 minute miles I tend to aim for a time half way i.e. 6:30 miles.
The plan is 16 weeks long and changes as you progress but a typical week is along the lines of:
Monday - Rest
Tuesday - Shorter interval type training: 200m/400m repeats, 1 or 2 mile blocks with a short recovery then repeat, etc.
Wednesday - A slower (8min/mile) run of 8 - 12 miles.
Thursday - A faster shorter run of 4 - 6 miles at 7 to 7:30 avg.
Friday - Rest
Saturday - Parkrun (Fast as you can)
Sunday - Longer, slower run of 18 - 22 miles at 8 avg.
All the details can be found here: https://www.dropbox.com/s/dc53c3bma79gzwr/Marathon%20Plan.xlsx?dl=0
Aside from 1 weeks skiing early in February the plan has been followed to the letter with no injuries either. Following the plan forces you to mix up your training and (for me anyway) I find you get better results than going out and doing distance runs at the same pace all the time.
As well as building up my endurance, I have noticed that over shorter distances my times have come down - comparing the interval type training I did for Gosport last year I am quicker again - and my Parkrun times have also been coming down where I thought endurance training was meant to take the edge off your pace over shorter distances.

Getting to mile 25 as then you know you are nearly at the end :) Being able to have a beer as well having had no alcohol since the plan started in January.
Speaking to people who have run London before, the atmosphere is meant to be very different to a club event with supporters pretty much all the way round the course and a lot more noise. Plus the sheer number of people taking part.
What are you expectations?
Third time lucky after North Dorset (blowing up due to a massive hill at mile 21) and Portsmouth (last minute entry so not enough training).
The first goal is to get round without any walking along the way. So assuming I achieve that main aim is to complete the marathon in no more than 3h30 which is an 8 minute mile average across the whole distance. All the long runs I have been doing have been at this pace which is faster than the plan suggests but the theory is that if I am used to running distance at that pace then I can carry it through on the day.