>> many of today's startups don't actually sell anything. They have a feature, not a business. Is Path really an eCommerce site? Hipster? <<
I was referring to the term 'eCommerce' in a somewhat broader context; a context in which eCommerce is equivalent to (gosh! I can't find the 'equivalent to' symbol on the keyboard - not even with the Alt+Num Pad key combinations - can you beat that!!!):
Physical goods / soft (digital/electronic) goods / advertising
>> ...ads aren't exactly a "product". They're an extra level above your service, and are notoriously much more difficult to pull off successfully <<
Partly agree, partly disagree.
This boils down to how you define a 'product'.
In my books, a product is something that you - or someone else - makes that others would be/are willing to pay (money) for. If a web site can generate advertising inventory (via traffic/eyeballs/members) that someone is willing to purchase, that is (nearly) as much of a product as a car/laptop/pizza/pair of nike shoes.
Think about this: If ads weren't a product (that sold for $$), where do you think Google would be today?
Now, if you say that Google is a (big?) part of Bubble 2.0, you just could be on terra firma there, but you'd find yourself hard-pressed to convince many people (myself included) of that.
>> and [ads] are notoriously much more difficult to pull off successfully <<
This, probably, is the most valid (such as it may be) point of your whole argument so far, with certain reservations.
What you probably mean here is that ads on typical social networking/forum web sites are generally low paying and if this is what you're saying, I'd agree with you whole heartedly. (We have a [regional] SN site averaging about 1M page views a month that generates < $100/mo on ad revenues. Although at no point during the 4+ years since we launched it have we really focused on revenue generation/maximisation, to be fair to the argument, that's neither here nor there).
>> Selling products, however, is much more concrete. <<
No argument with that, but as I mentioned above, it depends on how do you define a "product".
Back it comes to you now. :-)