By TWG_TECH4 in another thread:
For next generation watch; there are 3 models:
501: Basic, simple training functionalities, trainer function (like virtual partner), 50m water resistance, 2 weeks @ watch mode. Lowest Price!
503: Entry, interval/ muti sports, trainer function (like virtual partner), 50m water resistance, 2 weeks @ watch mode. Middle Price!
505: Professional, interval/ muti sports, trainer function (like virtual partner), 50 m water resistance, 2 weeks @ watch mode. Supports 2.4G HR and Candence and power meter! Highest Price!
They all use Training Gym-Pro, different to muti sports to Training Gym.
For Outdoor Traveling:
GH-561: Smart Routing, 3 Axis E-compass, find waypoints.
Use Travel Manager SW to plan route, waypoint and managed as data base.
MuzLog: The future model, will consider to MP3+ data logger and geotagging function.
SW: Immageo as a free ware, you can refer to http://www.easydevices.co.uk/main.asp?sitepages=Downloads. It is apprecaited if provide ideas.
Looking forward to hearing everybody comments.
Geoffrey 
Here are my first comments:
Seems like nice watches, depending on GPS-battery time I say they seem to fulfill all my current training needs Ill soon try the "ultra way of life/running" and like extra battery life or easy ways to charge it on the run, e.g. a short battery cable and a battery pack will probably also work if cable sits firmly in the watch e.g. like today and not some big desk-stand where you put the watch and it will be charged/synced that will not work on the run.
If I understand you correctly (please correct my wrong assumptions):
501 will be similar in functionalet to gh615/gh626 (but with virtual partner) and match the Garmin 405 line with long nonGPS battery time but with much better water resistance. (size and weight and design is still unknown) (HRM belt?)
503 is a 501 + multisport stuff (whatever that means) and interval programs. (HRM belt?)
505 is a 503 with a Candence and power meter. (power meter = HRM belt??) e.g this will match Garmin 310XT product line but with great none GPS battery time. Unknown if it will match the GPS battery time of Garmin 310XT
GH-561 is for hiking not training.
Above I only talk about functions I assume that "design" may differ between the products above.
The virtual partner and interval programs are great and I'm currently trying to start to train intervals and have not yet manage to figure out how to do this in a smooth way with the current product line. The virtual partner will be great on races if you can set you "dream" time and then easily see if you are behind or in front of the intended goal time. Currently I use average pace for this but it's hard to tell exactly how far behind you are.
As I see it you seem to have a product line matching and in some way are better then the Garmin product line (they seem to be the "big" name in the GPS training watch segment), as for polar/suunto I have never looked at them so closely as they have the GPS in an extra HW unit so they have never been compelling to me. I don't think there are other brands even close to you and Garmin all the other stuff I have looked at seem to only log (without a nice info screen) or lacking on other areas but I might have missed one.
I have never used a Garmin 305/405 so my comparison is just from what I have read from the net. I rate gh615 a realy good first try gh625 as near enough to Garmin 305 in most aspects (better in some and worst in some) but it still miss some features like virtual partner and I also think Garmin 305 has some interval program. The 50x series seem to match Garmin's new line but be seem to be better in all aspects. As none of 50x or Garmin 310XT is released yet we can't compare everything but it seem very promising.
A few questions: (it OK not to awnser these it you have some marketing "date" when to go public, just tell us in that case)
1. Will there be a Candence meter for running or only bicycle for the 505? (maybe the market for these is too small it would be nice if you could just tap-in and listen to the cheap nike foot pod)
2. Any hints on the aimed GPS Battery life?
3. Are the only difference between 503 and 505 the included extra measure pods?
4. Will it be the same HW e.g. can a user buy a 501/505 and later buy a Candence meter and it will work?
5. Will HRM belt be "coded"?
6. Will the measure HW be sold in a big package together with the 505 ot do you buy 505+HRM belt i a base package and then buy a Candence meter as a extra item?
7. I'm also interesting about when are you intending to public annonce these (or is there no special date planed yet?) so we can point other people to some nice info place (or here).
/Zingo