Its always difficult deciding wether or not to defer due to illness or injury, especially with the London Marathon.
I ran London last year with very little training. I had a baby at the end of September 2004, and after 12 weeks started training. By the end of January I was out with a really bad pelvic injury, had to get 2 months physio and started running at the beginning of April. 2 weeks later I ran the London Marathon and although it took me just over 5 hours its the best run/walk I have ever done. Instead of being with runners I ran and walked with loads of different people, some runners, some non-runners, people who have survived cancer!! eveyone.
Its my best marathon ever and I still look back on it fondly.
Perhaps though I was lucky and got through it with sheer determination. Most people thought I was crazy.
One thing though - you normally are sore after running a marathon but when I awoke on the Monday after London it felt like I had been in a car crash. I hurt in places I didn't even know existed.
Good luck with whatever you decide - if you don't do London this year perhaps try a half-marathon in May this year?
OOOOOO honestly - feel the burn. I felt all smug at the start as of course rain had been promised, and there I was in my pink bunny girl costume feeling all cool and dressed for the day, and suddenly at mile 3 I thought, oh oh suntan lotion!!!! Never packed any, and its the third time I have ran in that outfit, and the third time I've been burnt. [can you tell I'm blonde?]
I also had a temp. jigsaw tattoo for the Breast Cancer Campaign on my chest and of course now its left its mark (might come in handy for a few more men to sponsor me though :-) But my poor back, shoulders, chest, neck, legs, arms....... I have sympathy for you all.