Originally Posted by Klaxon
I would have to say go for it....The biggest perks for me
1. Being able to use the Business First/Elite Access counters for check in
2. Elite boarding (allows you to get your carry on in the overhead first)
3. Priority handling of baggage (huge on intl trips that are several days)
4. Access to Premium seating in Economy (You are closer to the exit)
I agree with the above, and would add the the 50% elite bonus means you rack up miles much faster as an elite. So, yes, its definitely worth it.
As for EUA: there's no question that upgrades are increasingly tougher to get on CO (for a variety of reasons discussed in this forum). Depending on your origination/destination points, your chance of EUA as a silver is generally low. But its a heck of a lot better than the odds of EUA as a non-elite (i.e zero).