I have answers to question one and two:
- This is true. However since version 2.8 Seaside is not a strictly “continuation-based” framework anymore. Seaside uses continuations in the flow module only. Since Seaside 3.0 the flow module is even optional. Also note that Seaside has strong Javascript support since 2005, this is long before mainstream frameworks started to add Javascript functionality. Today Seaside comes with JQuery and JQueryUI support built-in.
- Of course that depends on what you store within your session objects, but typically sessions are small (less than 20 KiB). Use the memory profiler in your application to determine the exact memory consumption.