Former Palm Centro user here, switched to Droid on release.

Palm to Droid:

Contacts, Tasks, Calendar Events, and Memos Sync:
use CompanionLink:

Sync your desktop software with Google and your phone

it's a time-limited trial, but you only need to sync once. I tried a buncha methods and this was the easiest and most comprehensive. It sends To-Do Lists to google calendar (not the most elegant solution but may have changed since then), and Memos to Contacts as |M| Your Memo Title |M| - also very inelegant but what can you do.

For Tasks:
I now use gTasks; syncs with Google tasks in Gmail; sync is wonky at times, but I like to have laptop access to my tasks list so the sync is key for me;

For Memos:
I now use GDocs Notepad; syncs with Google Docs; wish companionlink woulda linked my old memos to my google docs, but hey you can't have everything I guess. My new memos are now sync'd with Google docs, and I can easily archive them in google docs when i'm not using the memos as much; i still miss having all my old memos easily accessible, but eh I'll live =) I mean on second though Memo to Contacts actually works okay because search will pick up the titles of the memos...I guess i miss the "search all the memo text search" that palm had...

For Calendar:
Use google calendar; love it;

For Contacts:
Use Gmail contacts; takes a while to clean everything up after sync with companionlink, but having all your email, phone, physical addresses, etc in one place is unbelievably awesome.

Cheers!