Are you looking to develop or flip/resell the domain? if development is what you're after, City+service/product may be lucrative, but I echo "scandiman", when it comes down to resale value, be careful and don't go crazy registering everything. I posted the following info in another thread...
http://www.namepros.com/dot-mobi/306926-whats-the-status-of-your-watchlist.html
not sure if you'll be able to glean anything, but if you're looking for ideas to register, it might help a bit:
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I add to my watchlist every day and each day it also gets some names removed that have been regd. I have now compiled nearly 30,000+ domains that have been registered by others that were on my original watchlist and it grows everyday. There is still gold out there, don't let anyone tell you otherwise. I still register about 5 per day on average.
here's a good example, I live in the Washington DC area and many prime domains are gone, many City+service/product are also gone and yet there are very simple but important domains still available...
i.e. One I just registered, literally 5 minutes ago deals with a local info guide I'm planning on developing around user-generated content. There's major development underway in the Southwest DC area, and it is always referenced as "SouthWest DC" and of course "SWDC"... I couldn't believe that both domains were still left unregistered... so I grabbed both:
SouthWestDC.mobi & SWDC.mobi for reg fee. $17 total for 2 domains that I expected to spend a bit more on emailing owners or at auction. For anyone living in the DC area, they will realize that these domains are amazing but most importantly need to be developed and can be of much use to natives/tourists. Plenty of real estate listings, restaurants, nightlife, events, etc.
I was also able to register today: MetroStop.mobi & MetroStops.mobi to provide bus/subway mapping info for commuters, etc.
I would have easily paid $100+ each for all 4 domains I listed because they perfectly suit my development needs and are definitely applicable to mobile usage.
So don't let anyone tell you guys otherwise, they is still gold out there. If you're in this to buy to resell, be careful, but there are still some opportunities for quick flips... if you're a developer, the hardest part about .mobi is finding the right people & having the time to get the job done... the domains are out there.
For those of you that are still lost and can't find good names to reg, look to your local market, steer away from trademarks, etc and look for important locations or major tourist destinations in your area or for city+service/product domains... but don't go too crazy...
good luck to everyone.
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