I've you've noticed the standard $10 creeping up to $15 for Xbox Live Arcade games, you're not alone. Microsoft has acknowledged that the average price of XBLA games is rising, but also notes that the average review scores are rising along with it, reports GamesIndustry.biz.

"If you look at Live Arcade, and do the math, and look at the publicly available sales numbers, you can see that average prices on XBLA have crept up over the last few years, which has been an interesting trend because on some app markets there's been a race to zero as fast as possible," said Xbox Live Arcade portfolio director Chris Charla.

"We've seen a little bit of the opposite happening," he continued. "I don't really know where prices are going to go - ultimately, that's set by the market - but it has been really gratifying to see that people are willing to a premium price for digital content [sic]."

By the numbers, 21 of the 86 games in 2009 were $15 (1200 MSP), or about 24%. In 2010, that rose to 27/85, or about 32%. This year's figures aren't complete yet, but it already has 20 games confirmed at the $15 price point, so it will likely surpass last year again.

But it's not all bad news. Charla claims that the Metacritic score for XBLA games has risen as well, by a full 12 point average since 2008. "Sometimes, when [developers] talk about Live Arcade they're like, 'We want to do a boxed quality game on Live Arcade', and I'm like, 'What does that mean?' I can point at a bunch of 38 and 42 and 56 metacritic scoring boxed games, so it actually kind of pisses me off." Charla argues that games like Limbo or Castle Crashers are "as good as anything on the market."

Gamasutra looked at some of the top-selling XBLA games of the last six months, by analyzing leaderboard data. Dead Rising: Case West and Full House Poker were the standout hits, at over 200,000 each. A World of Keflings and Torchlight both nearly hit that mark as well. Gamasutra notes that some games may have sold well, but lack leaderboards, so it's hard to tell using this method.