How do you see the issue of HTML5 where the source is available to the client?
So there will be very little you can do to protect your solutions?
It really depends on how you implement the solution i.e. They either see just the generated code or everything. It's good to remember that by its very nature / design HTML works on reconstruction via a set of instructions...
Some might say that this is a bad thing, however therein lies the very power of the technology i.e. its ability to be adapted by the client.
Before I carry on with HTML, let me at least give merit where it's due; had it not being for Macromedia and Flash, the HTML industry would most likely not have been adequately motivated to move things ahead as quickly as they did. For me It's served it's purpose, as it no longer can attest to being fundamentally better than the HTML standards.
Flash was never anyway inherently safe wrt to your IP -- e.g. a simple google search will reveal the prevalence of dissembler apps.
The fact that HTML is being driven forward by more than just one company will ensure its adoption and success, inevitably the Adobe capital to support flash agents everywhere must have exceeded their revenue from the toolsets -- hence the decision to support a framework where the costs and responsibilities are distributed (for example with HTML5, poor experiences on Android will not be blamed on Adobe -- that now falls on Google, Samsung, Motorola, etc...)
On a side note: consider how many users we previously alienated with sites that only offered content in flash e.g. Consumers with only a low cost mobile device, blind users (no text to voice capability), etc...
Picking up on IP protection again -- HTML5 portals and app-like implementations are today heavily reliant on backend integration with services e.g. Ajax, jQuery, etc... -- the point being that in order to replicate / copy your solution the "pirate" would need more than just the generated & obsfucated client code to succeed.
That said, HTML5 and CSS3 is not without it's warts, js being one of the worst; followed closely by the lack of tools to simplify content creation, etc...
Still I believe many of these problems will be resolved in due course by companies like Adobe and their rich history of creating these toolsets.