Taichi 'Tai' Yagami is an 11-year-old who is an equivilant of Fushigi Yuugi's Miaka Yuuki in the Digiworld. Brunet, cute, outgoing, and brave -- but also brute, gluttonous, foolhardy as you want.  Nothing so different of the typic male lead in the typic shonen series, BTW (think of Shurato, Seiya, Duo, Hanamichi, etc). 

At first he thinks this Digi-gig is all a game, so he acts brashly and quickly and takes his accompaining Digimon, Agumon, in the same wrong/right way; it's not until he's entrusted with the Tag and Crest of Courage (and sees the CONSEQUENCES of his actions), that he starts to think things better, and specially since he takes conscience of his great responsability as the so-called Leader of the Digidestined. Taichi is also protective of everybody in the group (specially Hikari, Sora and Agumon), rather forgiving (ask Yama), and ready to take challenges at hand even if it takes risks. 

In Digimon 02, 14-year-old Taichi is basically the same guy, more mature and down to earth. He's the star of his soccer team and it seems that he seriously thinks of becoming a professional player. He and Yamato are still very close friends (or more? It's for you to decide...). 

Hum, do you realize that they hardly have a single time to really interact? Jyou seems more intrested into talking to Mimi or Yamato, not into following the lively goggleshipper around, being the conservative boy that he is. In turn, Taichi would bore himself to death with Jyou and his books constantly near to him, and even when he cares for him (Tai immediately sticked by Regular Jyou when Yamato insulted him in 'Weregarurumon's Dinner'), I don't see this going beyond friendship. 
 
 

Let's face it: Mimi has no place, IMHO, in the Taichi sweepstakes. Sora and Yamato are much more ahead on it, so Mimi may just shrug at the thought and turn to a closer guy to hit on him. The only MiChi hint I remember is when Taichi teases her at the call of 'Please come here to us, oh Princess!' or something in 'Sora's Crest of Love'.  Other than that, nothing. Mail me if you've found some, ne? 
 
 

Early on I said that Tai would be bored if he has to stay long time with Jyou, ne?  Hum, do you think it applies to Koushiro, too? NO! For a somewhat strange reason, Taichi is quite close to Kou-chan (though not so much as to Yamato), and when they co-work, it actually results kinda well. Taichi is the brawns, Koushiro is the brains, and it seems that other than Yamato, Koushiro is the one who better understands Taichi. He knows of Tai's great trauma with Hikari's frail health, after all, something even Yama-kun doesn't know of. So if Yamato may want to settle down with Jyou, possibly Taichi can take Koushiro (and Sora with Mimi? Hey, why not?).