If you're looking for a stealthy, strategic, tactical PSP shooter, Tactical Strike has what you're looking for.
Bad: teammate AI can sometimes be a little dumb, but most of the time they listen just fine. In campaign, when capturing and escorting in-game characters, they usually decide to sit right in front of your squad, resulting in their death due to crossfire - instead, you must tell them to stay behind until the firefight is over, then have them follow you). After commanding your squad to move somewhere (which is done practically every second of the game), your squad constantly says one of few annoying lines such as "Bravo is mobile"; this gets rather annoying very quickly. Same old stories as past SOCOM games (military leader/mercenaries threaten civilian life..blah blah blah). Repetitive game play in each level (e.g. battle mercenaries while searching for someone, only to arrive at the destination and for them to have escaped, but also leaving a clue behind to trace them down again, etc., etc.), objectives on map are not clear where they are located especially when there are different levels on a map, which led me wandering around aimlessly for a while on some levels.
Online: Unfortunately the online play in Tactical Strike is non-existent. There are only about 30 people playing online. I wasn't even able to find a game to join.
Bad Hype: SOCOM: TS has gotten a lot of bad hype by many SOCOM players, especially the Fireteam Bravo 1 and 2 fans. Tactical Strike can't be compared to the Fireteam Bravo series because they are different types of games. FTB1 and 2 are 1st/3rd person shooters and TS is a tactical squad-based shooter. FTB fans just don't like the tactical game play.
Bottom line: If you like strategic and tactical shooters, Tactical Strike is worth it. If you're more into the Fireteam Bravo series, wait for FTB3.