The SDHC will not speed anything up unless
you boot from it. Extending VM won't speed
anything up either - it just allows more
concurrent apps before Maemo starts
suspending them.
As for mem usage, AbiWord (2.4.6 - 2.6 should be better) didn't make much visible difference in the mem status bar thing. From what I can see, it takes 7 megs, compare to 24 for Opera right now. Gnumeric takes 10, looks like. N800, OS 2007.