A few random thoughts on the topic having recently delved into it a bit:
1) On the topic of women, there is a source brought in the Nitei Gavriel that brings the din based on a pasuk. In the 9th perek of the Megillah, Mordechai sends out a letter to the yidden about Purim. Then Esther writes down as well (9:29). This time Purim is not spelled with a vav. Indicating that though women are obligated like men in the mitzvos of Purim – there is an exception. The din of drinking.
2) Hagahos Maimonos brings the Ravayah that says drinking is a mitzvah b’alma but NOT a chiyuv. In other words, it seems it is a hiddur or perhaps the ideal way to have one’s seudas Purim – but one can fulfill their mitzvah of a seudah on Purim without becoming drunk (or drinking at all). Though drinking really should be taken quite seriously (see above posts ;-)) because the mitzvos of Purim are divrei sofrim and divrei sofrim one has to act in according with a din Torah (so safek – l’chumra) and the gemara does “chayav” – making it a potential situation where one has to go ideally like the most machmir shita (again as safek divrei sofrim l’chumrah).
But, this Ravayah and the fact that the Archos Chayim brings the great avreirah it is to get drunk [as is known it leads to the most serious avreiros which one does not need a rishon to r’l know – not referring to Purim btw, just one sees by the goyim] (the Bais Yosef brings his opinion to CONCLUDE his discussion) – and the Rabbeinu Efrayim (the primary disciple of the Rif) learns the gemara that at least the extent of the din is lightened by the story of Rabbah and R’ Zeirah [one can says either he means no din at all or the din of “ad d’lo yada”].
The Gra for example in the biur haGra on the Rema (who says one can take a nap AFTER drinking a little more than normal) brings the gemara that H’ loves one who never gets drunk and to see the Haghos Maimonos. In other words, it’s not contemporary Gedolim under political duress making such statements – its Rishonim and Gedolei Achronim.
Saying that, it is quite obvious that if one can find a way to get drunk and not be m’vatel mitzvos (like davening, bentsching, and not doing inappropriate activity) – then it is not a din to poo poo. As the Gra implies, just drinking and taking a nap is a kula. It’s forced. It is a fitting to do according to the M’B because how else can one fulfill “ad d’lo yada” – except by putting themselves in danger. There are deep reasons (not sure what – but it is brought down) of ‘ad dlo yadah’ so the M’B while recognizing the pitfalls states one should at least take a nap. This is based on a Pri Megadim who gets from Pri Chadash that really the din is to get smashed but in our generations (ie the Pri Chadash – who lived in last half of the 1600’s) one should not do so.
The emes is though that there is another shitah that seems to the Machaber (as the Rema brings a yeish omrim – he must be stating differently) and the Bach as well as many other poskim including the Sfas Emes on the Gemara and R’ Yisrael Salanter.
The gemara is not saying the mitzvah is to go ‘ad dlo yadah’ – rather it is a mitzvah to drink and be someach in the inyan of Baruch Mordechai and Arur Haman (see the Taz for example and other holy Sefarim) and that simchah and joyous celebration is an obligation on the person the whole day. If they get to the point of ‘ad d’lo yadah’ – they’re patur. Not fulfilling but rather ending their ability to be involved in the mitzvah.
This opinion requires drinking more than usual (the Bais Yosef says just ‘m’at’ [a little more] than usual), the Bach says even drunkedness that one still has their daas [ie their still aware and thinking – just quite tipsy]. This is the reason the gemara used l’vsumei not the normal lashon shikar (which the Tur says – and the Shulchan Aruch switches back).
I have already written a lot, so I’ll stop
Freliechen Purim.