pawsplay
Hero
Though it also bears mentioning that my players, at the least, are a lot less likely to grab a prestige class than they were in 3.X. Even the sorcerers.
The Auld Grump
Our wizard decided, on the balance, to keep his Archmage levels, but it didn't make a huge difference. The Contemplative still works fine.
Monsters can be run as-is. Now, for a true converision, monsters may gain a feat or two, and monsters with low skill points and/or Int tend to gain a substantial boost. Between the different rules for cross-class skills and the smaller skill list, many monsters are able to cover Climb, Perception, and maybe another skill that struggled, before, to justify their Alertness feat.
I used plenty of converted monsters from the MMII and MMIII, the Fiendish Codeces, plus templates from Savage Species. with the Bestiary 2 out, my motivation to continue to do has receded.