No, they're not the same.
As someone previously pointed out, a solicitor-advocate can appear on behalf of his client in all courts: he has higher rights of audience. Most of the big City firm's litigation departments are taking steps to ensure that all their litigators have higher rights.
However, solicitors and barristers remain totally different branches of the profession. All that has happened is that the line between them has blurred slightly in certain circumstances.
It is certainly possibly to transfer between the two. I know people who have done it in both directions although it is relatively uncommon. Interestingly, the majority of barristers start out as solicitors here in Oz and transfer shortly after their career starts.
The reality is that the bar will continue to do the vast majority of contested court work, especially in the larger RCJ matters. The bar is cheaper and more experienced than solicitor-advocates.
If you're interested in doing high level civil advocacy then the bar is really the only option. I am not of the view that you will be exposed to decent advocacy opportunities (eg lengthy civil trials) by being a sol-advocate.
Let me know if you'd like to know more.
Chalks.