The US PlayStation Network update for this week is now available. And yes, finally, the Mercenaries 2 demo is live - they probably got stuck in traffic along the way - as well as the demo for Fracture. PSP owners also get two downloadable titles this week, both from D3 Publisher: PQ and Cube.

It's already the third installment for this five-part series listing 25 games that do not deserve to collect dust in the bargain section of any store. In this installment, we'll have a few games that come from reputable franchises, such as Metal Gear Solid Portable Ops and Tekken: Dark Resurrection. We'll also have an interesting puzzle/brain training hybrid in the form of PQ: Practical Intelligence Quotient, and other titles. Don't miss out on the entire list in the full article!

Thanks to German gaming news site GameFront, we got hold of a new list of release dates for PAL titles. The list has quite a few PSP titles in it, along with one each for the Nintendo DS and Microsoft's Xbox 360. No PS3 titles, though.

A couple of notable titles are The History Channel: Great Battles of Rome and Earth Defence Force 2017. Puzzle fans also get their own dose of gaming goodness courtesy of the PSP titles Cube and PQ: Practical Intelligence Quotient. Check the list below for the titles and dates.

May 25

• Final Fantasy Fables: Chocobo Tales (DS)

June 1

• The History Channel: Great Battles of Rome (PSP, PS2)

June 8

• Earth Defence Force 2017 (Xbox 360)
• PQ: Practical Intelligence Quotient (PSP)
• SBK-07 Superbike World Championship (PSP)

June 29

• Cube (PSP)

As previously reported, D3Publisher of America passes first exam and releases the puzzler PQ: Practical Intelligence Quotient for PSP.

Studies have recently shown that games can help increase your reaction time, help teach logic and extend spatial abilities. However all of these great wondrous educational experiences are usually disguised as shooting Nazi's in Return to Castle Wolfenstein or saving Princess Peach in Super Mario 64. However game like Practical Intelligence Quotient, tell a different story, boasting "100 3D puzzles that test gamers' logic, by challenging them to move blocks, pull switches, and avoid obstacles. There are 13 different puzzle types to tease brains, and users can post their "PQs" online and see how they stack against the rest of the world." PQ: Practical Intelligence Quotient by Japanese game developer Nowproduction is now on the market and retails for $29.99.