Looks like they're positioning the eTrex -> Colorado -> Oregon series more clearly as the handheld/trekking/very occasional use on the bike series and the x05 into the dedicated designed-for-bikes series...
Looks to me as though Garmin are going every which way - or maybe just slinging a lot of mud at the wall to see if some of it sticks.
Now there's the Nuvi 500 (and 550) - a ruggedised version of yer typical in-car satnav -
"nüvi 500 features driving, walking, bicycling and boating modes which customize your nüvi specifically for your method of travel. ... large, color display found in automotive units with the durability of an outdoor handheld. Sleek and slim, you can slip nüvi 500 into your pocket or backpack."
https://buy.garmin.com/shop/shop.do?pID=13424#battery is li-ion.
I've had a Garmin Colorado 300 for about 6 months now. I love it. Battery life is good.
That's the most positive reaction to the Colorado I've read for a long time - good-oh!
... touchscreen which is interesting. I wonder how well that will work in the rain, or if you're wearing gloves etc. And it could get scratched.
Oregon touchscreen is pressure-sensitive, so it works with gloves, or using tyre lever as stylus - but the downside is that it ends up dimmer/more reflective compared with the Colorado, and yes, may be vulnerable to damage.
[ lifted from Scott's Oregon 1st Impressions' page
http://garminoregon.wikispaces.com/