And if these handheld systems only have mediocre games, why are they selling so well?

Because the review system is simply broken. The lack of stanard criterion that can be applied across genres makes reviewing games extremely difficult in a unique way. The games are excellent, but the reviews do not reflect that. I could come up with a list of games that clearly should have a better score but don't because the reviewers fail to accept the game for what it is.

I can see that - when I'm looking to buy a DS game, I check people's opinions on messageboards and amazon reviews rather than metacritic.

90+ rated games? Bah!

Give me my 80+ rated games.

It's obvious that the review system is horribly broken and has been for a long time. The fact that a numerical score is attached to a review completely invalidates the review.

Unless a prominent reviewer comes around that completely ditches a mark/grade/score from his reviews, the system will be stuck with the current sheep that inhabit our review organizations.

 Yahtzee?

ps2 had all the major third party support.

but also neither psp/ds gets major games unless are from nintendo.

they both get either spin off, or remade.

psp is getting some sequels from square and a ff13 title but that its.

Mainly because (for obvious reasons) a handheld system is not about the latest and greatest graphical technology, the games are generally (far) less hyped, and as a result most reviewers are willing to see a game for what it is.

Another way to look at this is "Why are so many games that have many large flaws, serious issues, and are (very) generic receiving 90%+ scores on the HD consoles?"

Tons of handheld games are under-rated.

That said, the PS3 only has 5. You shouldn't infer that non 90+ games are mediocre. That's childish and ignorant. Are you those things, or are you a reasonable adult?

It's really difficult to make a really good game on a handheld. There just aren't enough resources/technology to make it possible. However, the amount of good games (70/80+) is more than enough to satisfy your handheld gaming needs.

Plus, reviewers inevitably end up comparing handheld games to console games. Obviously, it doesn't end well for the handhelds.