I've had success with humans, and to a lesser extent dwarves and halflings. The human skill points and feat are so useful that it is the default for almost any character concept (which is as it should be). You only play something else if you have enough skill points already (which almost never happens) and aren't terribly dependent on a certain feat or feat chain. I've played and seen many humans, obviously, including one in my current game.
Dwarves make great tanks-fighters and barbarians-and decent clerics, wizards, or rogues. The crafting and appraise bonuses are useless in most campaigns but their overall toughness is great. They're good at what they should stereotypically be good at for the most part. I've seen/played a few. Got a dwarf PC in my current game-going very well.
Halflings are great rogues or casters, but their foot speed is a pain and they can draw some flak from players of bigger characters. I've played some but my PCs never seem inclined.
Gnomes are good clerics or illusionists, but it's hard to take them seriously despite their reasonable mechanical attributes. I wish I'd used them more. Had a decent gnome cleric PC once.
Elves are good at being scouts but not at anything else (saving some cleric builds I suppose). The weapon profs are worthless for 95% of characters, who either have the prof anyway (fighter/ranger/etc.) or will never be good with bows anyway (wizards). I can't remember the last elf PC I saw (actually, I can-it was when 3.0 first came out. Combat rogue, really powerful).
Half-elves are by far the weakest race, with no real strengths or weaknesses they're like pathetic humans. Never had one of those to my recollection, despite my efforted fixes.
Half-orcs are decent fighters or barbarians, but people who want strength usually go for small-ECL monster races. They need a few more bonuses to make them worthwhile. I think I played one briefly a long time ago.
My players would rather play humans or monster races then mess around with the core ones. The UA paragon classes strengthened this-humans are now great for caster multiclasses, anyone who needs feats or skill points, or anyone who can't suck up the other races' various penalties.