With the upcoming SirfStar IV chip, mobiles will have drastically reduced battery life when using their GPS. Therefore they will make a much bigger threat to the handheld GPS market and it will be necessary for Garmin to improve their products. Here are some suggestions, especially regarding internet connectivity.
1) Live geocaching (internet connectivity) - As it is now, you have to connect your GPS to a computer to download the nearest caches. Mobile phones have the ability, with programs like "Geocaching Live", to connect to geocaching.com and look for the nearest caches when you are out in the field and haven't made any preparations. This will come in handy when you go on unexpected and spontaneous trips anywhere. You can also chat with other geocachers and I think you can even log your found caches. Maybe the GPS also should be able to automatically update Facebook/Twitter directly when you find a cache. Garmin should look deeper into internet connectivity when already outside with the GPS unit.
2) Improve geotagging - This may be more of a certainty. The camera in the Oregon 550 is a step in the right direction, but mobile phones nowadays often have at least 5 mp cameras. I would love to see a successor to Dakota 20 with a camera implemented. Also the ability to upload pictures directly to geocaching.com.
3) Improve screen visibility - In sunlight the visibility within some handheld touch screen GPS are not good enough. Implementing touch screen is great though, but Garmin should look at options in how to improve screen visibility. I also want them not to limit the brightness settings too much, all units should be able to reach the same brightness. People know that the brighter the screen, the more battery it drains. Making a GPS screen not as bright as others is therefore unnecessary.
4) Easier paperless geocaching - I would like to be able to change between map/compass and cache information with just one click, when doing paperless geocaching. This will make it much more user friendly than instead of having to press several times. Maybe Garmin should implement customizable shortcut buttons?
EDIT: I think I posted in the wrong forum section?!