In reply to All:
This is a promising start
For those not very familar with the trois mont traverse, it begins at the Cosmique hut on the Col du Midi and takes in Mont Blanc du Tacul, Mont Maudit then finally Mont Blanc.
The ascent usually takes 6-7 hours at a steady pace with minimal stops. The descent route from the summit is usually the Gouter, and takes about 4 hours from the summit to the Nid d'Aigle train station, from where we'd then catch the train back to Chamonix.
It's in season from early June right through to early September so that'd give us a lot of options in terms of fitting around other summer plans.
In terms of difficulty- technically it's only graded a PD, but there are some pretty steep sections of ice and neve as you ascend the north face of Mont Blanc du Tacul, and approaching the Col du Maudit towards the top of the north face of Mont Maudit is a 50 degree section which is apparently the crux of the whole route. Other than that, from what I've read it's a case of being able to maintain a steady pace at altitude for a prolonged period of time, so it comes down to fitness and stamina more than technical ability.
I was planning to head out there for a week, do a couple of training/acclimatisation peaks, get a couple of nights spent at altitude (in huts rather than bivvying) and then make an early start either 1 or 2 days before the flight home depending on feeling, weather etc.
There's some good info here including photos of the steeper sections:
http://www.summitpost.org/route/202778/mont-blanc-3-mounts-traversee.html
http://cosleyhouston.com/mont-blanc-traverse.htm
I don't want to mislead anybody so I should point out that I'm by no means experienced when it comes to winter climbing, having only ever tackled a few grade 2-3 routes and only using ice axe and crampons a few times.
This will be my first alps trip, but from reading into it and talking to people who've done it, I think it's more than realistic for a 1st trip to the alps, especially if the week before is spent on training/acclimatisation climbs and practicing.
Anybody who's still interested, send me an email and if we get a few of us I can cc everybody in and try to sort something out.