I'm playing a druid (lvl 41) now and I must say that for soloing this class is pretty good.
Here is a quick list of things I've done I've done in the last week or two that support my claim:
- At lvl 37 I solo'd lvl 41 raptors in STV repeatedly for a quest with little downtime
- At lvl 39 I took on a lvl 44 naga in STV (as a joke) in front of friends and won...I have never killed something that much higher than me prior to this with any other class...I must say I got lucky though because a fair amount of my attacks landed and usually at that lvl difference you can expect to miss much more than you hit

...I don't think this win would be a repeated one
- this morning at lvl 41 I took on an elite lvl 42 ogre in STV....cat form long enought to get 5 combo points..put the dot on...heal...shift to bear and hold on

- also this morning I was killing skullsplitters (lvl 40 ish)....I was consistantly taking on the 3 lvl 40 that patrol (usually 2 warriors and either an axe thrower or magic guy)
- as far as low lvl instances go...I solo'd deadmines repeatedly at lvl 37...I don't know how this compares to what other classes have experienced but I know I couldn't have done it with my warrior at that lvl for sure.
You have a wide variety of options as a druid when fighting or fleeing. Even If I get into trouble I usually (not always) can get away (instant cast travel form or cat form speed burst) heal and come back. I feel that I do good dps in cat form now. I am feral spec with mostly agility and either strength or stamina gear so I have very little mana but I only use it for some quick healing and shape shifting for the most part.